【High Quality】Adapter Using ultra precision CNC machine tools,sophisticated material,high intensity,good operation stability, and by the application of a matte black electroplated finish., which withstands corrosion and other abrasive elements often encountered in outdoor photography. | 【Compatible with】All 95mm camera lenses & 105mm accessories(UV,CPL,ND,Lens Hood,Threaded Lens).Your lens thread size will be printed underneath your lens cap or written somewhere on the lens barrel.This number is always prefixed by a"O"(diameter) symbol. | 【Product Description】The first number of an adapter ring is always the lens thread size,the second number is the filter size of the accessory.If the first number is bigger,it's a Step-down ring What is a step up ring?Step up rings,also known as adaptor rings,allow you to use filters and accessories that are not the same size as your cameras lens. | 【Notice】95mm lens: Make sure your Camera lens size is 95mm, and the filter size is 105mm, so choose the 95-105mm adapter ring.Your lens thread size will be printed underneath your lens cap or written somewhere on the lens barrel. Make sure you order the correct size otherwise it will not fit your lens. | 【Quality assurance】We offer 90 day warranty after-sales service,if you meet any problem,please don’t hesitate to contact us.Your shopping experience is important to us.

【High Quality】Adapter Using ultra precision CNC machine tools,sophisticated material,high intensity,good operation stability, and by the application of a matte black electroplated finish., which withstands corrosion and other abrasive elements often encountered in outdoor photography. | 【Compatible with】All 95mm camera lenses & 82mm accessories(UV,CPL,ND,Lens Hood,Threaded Lens).Your lens thread size will be printed underneath your lens cap or written somewhere on the lens barrel.This number is always prefixed by a"O"(diameter) symbol. | 【Product Description】The first number of an adapter ring is always the lens thread size,the second number is the filter size of the accessory.If the first number is bigger,it's a Step-down ring What is a step up ring?Step up rings,also known as adaptor rings,allow you to use filters and accessories that are not the same size as your cameras lens. | 【Notice】95mm lens: Make sure your Camera lens size is 95mm, and the filter size is 82mm, so choose the 95-82mm adapter ring.Your lens thread size will be printed underneath your lens cap or written somewhere on the lens barrel. Make sure you order the correct size otherwise it will not fit your lens. | 【Quality assurance】We offer 90 day warranty after-sales service,if you meet any problem,please don’t hesitate to contact us.Your shopping experience is important to us.

✪Compatible with Panasonic Lumix G9 G7 G6 G5 G3 G2 G1 G10 ,GH6 GH5 GH5S GH4 GH3 GH2 GH ,G95 GX1 GX2 GX7 GX8 GX9 GX85 GX850 , GF1 GF2 GF3 GF5 GF6 GF7 GF8 GF9,GM1 GM5 Camera with Micro 4/3 mount camera,etc. | ✪Compatible with Olympus E-M10 Mark IV / E-M10 Mark III / E-M10 Mark II / E-M10 / E-M1 Mark III / E-M1 Mark II / E-M1 / E-M5 Mark III E-M5 Mark II /E-M5 E-P1 E-P2 E-P3 E-P5 E-PL1 E-PL2 E-PL3 E-PL5 E-PL6 E-PL7 E-PL8 E-PL9 E-PM2 E-PM1 PEN Cameras and M43 Mount Lenses,etc. | ✪All of the caps are made of high quality ABS plastic，they can be easily put into the camera bag or pocket, easy to carry.The use of front and rear lens covers can effectively prevent the lens from collision or accidental damage to protect the lens. | ✪Camera cap keeper with elastic band stretches to fit snuggly around the circumference of your lens，Microfiber Cleaning Cloth made of premium microfiber materials Ideal for cleaning oil, fingerprints, smudges, and dirt off eyeglasses, laptops, tablets of all brands, smartphones, and any other LCD or touch screen. | ✪Package inlcudes: 2 x Body cap, 2 x Rear lens cap，4 * Lens Cap Keepers;1 * Microfiber Cleaning Cloth

X Mount Rear Cap,X Mount Body Cap, Designed for Fuji X mount lenses.Body cap fits Fujifilm X mount mirrorless cameras such as Fujifilm X-T5, X-T4, X-T3, X-T2, X-T1, X-T10, X-T20, X-T30, X-S10, X-T200, X-T100, X-PRO3, X-PRO2, X-PRO1, X-A10, X-A3, X-A2, X-E3, X-E2S, X-E2, X-M1, X-H1, X-H2, X-H2S etc. | Rear lens cap protects the rear glass element and electronic contacts from scratches, dust, water and fingerprints. | All of the caps are made of high quality ABS plastic，they can be easily put into the camera bag or pocket, easy to carry.The use of front and rear lens covers can effectively prevent the lens from collision or accidental damage to protect the lens. | Camera cap keeper with elastic band stretches to fit snuggly around the circumference of your lens，Microfiber Cleaning Cloth made of premium microfiber materials Ideal for cleaning oil, fingerprints, smudges, and dirt off eyeglasses, laptops, tablets of all brands, smartphones, and any other LCD or touch screen. | Package inlcudes: 2 x Body cap, 2 x Rear lens cap，4 * Lens Cap Keepers;1 * Microfiber Cleaning Cloth

The Body Cap fits PRAKTICA MTL3 MTL5 Camera,for PENTAX SP Camera etc;The Rear Lens Cap fits Carl Zeiss Jena Flektogon 35mm F2.4 Lens,Meyer-Optik 50mm f/1.8 Lens,PK SMC takumar 55mm f/1.8 Lens,Helions-44-2 58mm f/2 Lens etc. | Rear lens cap protects the rear glass element and electronic contacts from scratches, dust, water and fingerprints. | All of the caps are made of high quality ABS plastic，they can be easily put into the camera bag or pocket, easy to carry.The use of front and rear lens covers can effectively prevent the lens from collision or accidental damage to protect the lens. | Camera cap keeper with elastic band stretches to fit snuggly around the circumference of your lens，Microfiber Cleaning Cloth made of premium microfiber materials Ideal for cleaning oil, fingerprints, smudges, and dirt off eyeglasses, laptops, tablets of all brands, smartphones, and any other LCD or touch screen. | Package inlcudes: 2 x Body cap, 2 x Rear lens cap，4 * Lens Cap Keepers;1 * Microfiber Cleaning Cloth

【Soft Highlight Flares, Lowered Contrast】NEWKS 67mm black diffusion 1/4 filter with dreamy cinematic effect helps reduce highlights and lower the glare, making the skin look smoother and gives the tone a hazier and softer look. The hazy film effect can be better realized, showing a dreamy film effect. Ideal for portrait photography, video recording, and vlog videos. | 【Import Optical AGC Glass】Made of Japanese AGC HD optical glass with 89% light transmission and a high definition quality, creating a soft quality of light and pastel effect. | 【Multi Layers Nano Coatings】30 Multi-Layer CoatedBoth sides of the glass with nanometer coating, no color cast, ensure the light penatrate the glass evenly, showing high definition image quality.Waterproof & Scratch Resistant Coating | 【CNC Non Slip & Ultra Slim Frame】With aviation aluminum, the width of the frame measures only 3.3mm, ultra-slim frame with no dark corners on the wide-angle and telephoto lens. CNC-non slip design for efficiently removing and installing the filter. | 【Choose the Right Filter Size】The NEWKS Filter comes in different sizes. This 67mm filter can only work with an 67mm camera lens. Please make sure that your camera lens filter thread and the 67mm filter set match ，the number is always preceded by a "ø" (diameter) symbol. Check for additional sizes to fit your camera lens.Here are 4 filter strengths available from weakest to strongest: 1/8, 1/4, 1/2 and 1, please choose the right one you want.

【Protective UV Filter】 This UV filter reduces haze and minimizes ultraviolet (UV) rays while improving contrast. Perfect for capturing high altitude and snow photos without the bluish cast. Keep this filter on your lens to protect against dust, scratches, and bumps | 【High-Quality Optical Glass】The quality optical glass protects your lens from dirt, scratches, fingerprints, and unexpected damage,Nano-Coatings Featuring 16 layers of optical coatings and a light transmittance of up to 99.4% (and a minimum light reflectance of less than 0.3%), the multicoated UV filter blocks out ultraviolet rays ranging from 300nm to 410nm to reduce flare and ghosting while ensuring accurate color rendition | 【Strong Lens Frame】 Made of aluminum-magnesium alloy, the filter frame is strong and durable. With precision manufacturing and a matte black anodized finish, the screw-on filter is easy to use and has less reflections from the metal filter frame. The 0.24”/6.1mm thick filter measures only 0.13”/3.2mm in depth when screwed on your lens to avoid lens vignetting-ideal for wide-angle lens and telephoto lens | 【Super Slim & Non-Slip】 Super slim(only 0.13inch/3.2mm).non-slip design(trapezoidal pattern) ensure the friction is increased over a large area when rotate filter, very easy to install and remove the filter. | 【Compatibility】 Compatible with all 105mm lenses. Please find out your camera’s lens thread size before buying. The thread size will be marked on the lens or the lens cap with the ‘ø’ followed by a number

【Protective UV Filter】 This UV filter reduces haze and minimizes ultraviolet (UV) rays while improving contrast. Perfect for capturing high altitude and snow photos without the bluish cast. Keep this filter on your lens to protect against dust, scratches, and bumps | 【High-Quality Optical Glass】The quality optical glass protects your lens from dirt, scratches, fingerprints, and unexpected damage,Nano-Coatings Featuring 16 layers of optical coatings and a light transmittance of up to 99.4% (and a minimum light reflectance of less than 0.3%), the multicoated UV filter blocks out ultraviolet rays ranging from 300nm to 410nm to reduce flare and ghosting while ensuring accurate color rendition | 【Strong Lens Frame】 Made of aluminum-magnesium alloy, the filter frame is strong and durable. With precision manufacturing and a matte black anodized finish, the screw-on filter is easy to use and has less reflections from the metal filter frame. The 0.22”/5.5mm thick filter measures only 0.13”/3.2mm in depth when screwed on your lens to avoid lens vignetting-ideal for wide-angle lens and telephoto lens | 【Super Slim & Non-Slip】 Super slim(only 0.13inch/3.2mm).non-slip design(trapezoidal pattern) ensure the friction is increased over a large area when rotate filter, very easy to install and remove the filter | 【Compatibility】 Compatible with all 112mm lenses. Please find out your camera’s lens thread size before buying. The thread size will be marked on the lens or the lens cap with the ‘ø’ followed by a number

【Protective UV Filter】 This UV filter reduces haze and minimizes ultraviolet (UV) rays while improving contrast. Perfect for capturing high altitude and snow photos without the bluish cast. Keep this filter on your lens to protect against dust, scratches, and bumps | 【High-Quality Optical Glass】The quality optical glass protects your lens from dirt, scratches, fingerprints, and unexpected damage,Nano-Coatings Featuring 16 layers of optical coatings and a light transmittance of up to 99.4% (and a minimum light reflectance of less than 0.3%), the multicoated UV filter blocks out ultraviolet rays ranging from 300nm to 410nm to reduce flare and ghosting while ensuring accurate color rendition | 【Strong Lens Frame】 Made of aluminum-magnesium alloy, the filter frame is strong and durable. With precision manufacturing and a matte black anodized finish, the screw-on filter is easy to use and has less reflections from the metal filter frame. The 0.22”/5.5mm thick filter measures only 0.13”/3.2mm in depth when screwed on your lens to avoid lens vignetting-ideal for wide-angle lens and telephoto lens | 【Super Slim & Non-Slip】 Super slim(only 0.13inch/3.2mm).non-slip design(trapezoidal pattern) ensure the friction is increased over a large area when rotate filter, very easy to install and remove the filter | 【Compatibility】 Compatible with all 127mm lenses. Please find out your camera’s lens thread size before buying. The thread size will be marked on the lens or the lens cap with the ‘ø’ followed by a number

13pcs Step Up Ring Kit Includes: 26-30mm,30-37mm,37-43mm,43-46mm,46-49mm,49-52mm,52-55mm,55-58mm,58-62mm,62-67mm,67-72mm,72-77mm,77-82mm. The first number is always the lens thread size, the second number is the filter size of the accessory. If the first number is larger, it's a step-down. Compatible with Digital SLR camera lens.

【Protective UV Filter】 This UV filter reduces haze and minimizes ultraviolet (UV) rays while improving contrast. Perfect for capturing high altitude and snow photos without the bluish cast. Keep this filter on your lens to protect against dust, scratches, and bumps | 【High-Quality Optical Glass】The quality optical glass protects your lens from dirt, scratches, fingerprints, and unexpected damage,Nano-Coatings Featuring 16 layers of optical coatings and a light transmittance of up to 99.4% (and a minimum light reflectance of less than 0.3%), the multicoated UV filter blocks out ultraviolet rays ranging from 300nm to 410nm to reduce flare and ghosting while ensuring accurate color rendition | 【Strong Lens Frame】 Made of aluminum-magnesium alloy, the filter frame is strong and durable. With precision manufacturing and a matte black anodized finish, the screw-on filter is easy to use and has less reflections from the metal filter frame. The 0.22”/5.5mm thick filter measures only 0.13”/3.2mm in depth when screwed on your lens to avoid lens vignetting-ideal for wide-angle lens and telephoto lens | 【Super Slim & Non-Slip】 Super slim(only 0.13inch/3.2mm).non-slip design(trapezoidal pattern) ensure the friction is increased over a large area when rotate filter, very easy to install and remove the filter | 【Compatibility】 Compatible with all 37mm lenses. Please find out your camera’s lens thread size before buying. The thread size will be marked on the lens or the lens cap with the ‘ø’ followed by a number

Pro Version of Newks Product | Universal Studio Softbox Flash Diffuser.Converts the harsh light from battery-operated flash to a softer, diffused light, while reducing shadows and softening hot spots as shown in our testing photosCollapsible. | Set up and fold flat in seconds and store in zippered bag, making it ideal for location or studio use | Simply slip the softbox around the front of your flash unit | Note: Camera and speedlight are NOT included

【Protective UV Filter】 This UV filter reduces haze and minimizes ultraviolet (UV) rays while improving contrast. Perfect for capturing high altitude and snow photos without the bluish cast. Keep this filter on your lens to protect against dust, scratches, and bumps | 【High-Quality Optical Glass】The quality optical glass protects your lens from dirt, scratches, fingerprints, and unexpected damage,Nano-Coatings Featuring 16 layers of optical coatings and a light transmittance of up to 99.4% (and a minimum light reflectance of less than 0.3%), the multicoated UV filter blocks out ultraviolet rays ranging from 300nm to 410nm to reduce flare and ghosting while ensuring accurate color rendition | 【Strong Lens Frame】 Made of aluminum-magnesium alloy, the filter frame is strong and durable. With precision manufacturing and a matte black anodized finish, the screw-on filter is easy to use and has less reflections from the metal filter frame. The 0.22”/5.5mm thick filter measures only 0.13”/3.2mm in depth when screwed on your lens to avoid lens vignetting-ideal for wide-angle lens and telephoto lens | 【Super Slim & Non-Slip】 Super slim(only 0.13inch/3.2mm).non-slip design(trapezoidal pattern) ensure the friction is increased over a large area when rotate filter, very easy to install and remove the filter | 【Compatibility】 Compatible with all 40.5mm lenses. Please find out your camera’s lens thread size before buying. The thread size will be marked on the lens or the lens cap with the ‘ø’ followed by a number

【Protective UV Filter】 This UV filter reduces haze and minimizes ultraviolet (UV) rays while improving contrast. Perfect for capturing high altitude and snow photos without the bluish cast. Keep this filter on your lens to protect against dust, scratches, and bumps | 【High-Quality Optical Glass】The quality optical glass protects your lens from dirt, scratches, fingerprints, and unexpected damage,Nano-Coatings Featuring 16 layers of optical coatings and a light transmittance of up to 99.4% (and a minimum light reflectance of less than 0.3%), the multicoated UV filter blocks out ultraviolet rays ranging from 300nm to 410nm to reduce flare and ghosting while ensuring accurate color rendition | 【Strong Lens Frame】 Made of aluminum-magnesium alloy, the filter frame is strong and durable. With precision manufacturing and a matte black anodized finish, the screw-on filter is easy to use and has less reflections from the metal filter frame. The 0.22”/5.5mm thick filter measures only 0.13”/3.2mm in depth when screwed on your lens to avoid lens vignetting-ideal for wide-angle lens and telephoto lens | 【Super Slim & Non-Slip】 Super slim(only 0.13inch/3.2mm).non-slip design(trapezoidal pattern) ensure the friction is increased over a large area when rotate filter, very easy to install and remove the filter | 【Compatibility】 Compatible with all 43mm lenses. Please find out your camera’s lens thread size before buying. The thread size will be marked on the lens or the lens cap with the ‘ø’ followed by a number

【Protective UV Filter】 This UV filter reduces haze and minimizes ultraviolet (UV) rays while improving contrast. Perfect for capturing high altitude and snow photos without the bluish cast. Keep this filter on your lens to protect against dust, scratches, and bumps | 【High-Quality Optical Glass】The quality optical glass protects your lens from dirt, scratches, fingerprints, and unexpected damage,Nano-Coatings Featuring 16 layers of optical coatings and a light transmittance of up to 99.4% (and a minimum light reflectance of less than 0.3%), the multicoated UV filter blocks out ultraviolet rays ranging from 300nm to 410nm to reduce flare and ghosting while ensuring accurate color rendition | 【Strong Lens Frame】 Made of aluminum-magnesium alloy, the filter frame is strong and durable. With precision manufacturing and a matte black anodized finish, the screw-on filter is easy to use and has less reflections from the metal filter frame. The 0.22”/5.5mm thick filter measures only 0.13”/3.2mm in depth when screwed on your lens to avoid lens vignetting-ideal for wide-angle lens and telephoto lens | 【Super Slim & Non-Slip】 Super slim(only 0.13inch/3.2mm).non-slip design(trapezoidal pattern) ensure the friction is increased over a large area when rotate filter, very easy to install and remove the filter | 【Compatibility】 Compatible with all 46mm lenses. Please find out your camera’s lens thread size before buying. The thread size will be marked on the lens or the lens cap with the ‘ø’ followed by a number

【Soft Highlight Flares, Lowered Contrast】NEWKS 49mm black diffusion 1/8 filter with dreamy cinematic effect helps reduce highlights and lower the glare, making the skin look smoother and gives the tone a hazier and softer look. And double side polishing technology ensures high definition within 550mm focal length. | 【Import Optical AGC Glass】Made of Japanese AGC HD optical glass with 92% light transmission and a high definition quality, creating a soft quality of light and pastel effect. | 【Multi Layers Nano Coatings】30 Multi-Layer CoatedBoth sides of the glass with nanometer coating, no color cast, ensure the light penatrate the glass evenly, showing high definition image quality.Waterproof &Scratch Resistant Coating | 【CNC Non Slip & Ultra Slim Frame】With aviation aluminum, ultra-slim frame with no dark corners on the wide-angle and telephoto lens. CNC-non slip design for efficiently removing and installing the filter. | 【Choose the Right Filter Size】The NEWKS Filter comes in different sizes. This 49mm filter can only work with an 49mm camera lens. Please make sure that your camera lens filter thread and the 49mm filter set match ，the number is always preceded by a "ø" (diameter) symbol. Check for additional sizes to fit your camera lens.Here are 4 filter strengths available from weakest to strongest: 1/8, 1/4, 1/2 and 1, please choose the right one you want.

【Protective UV Filter】 This UV filter reduces haze and minimizes ultraviolet (UV) rays while improving contrast. Perfect for capturing high altitude and snow photos without the bluish cast. Keep this filter on your lens to protect against dust, scratches, and bumps | 【High-Quality Optical Glass】The quality optical glass protects your lens from dirt, scratches, fingerprints, and unexpected damage,Nano-Coatings Featuring 16 layers of optical coatings and a light transmittance of up to 99.4% (and a minimum light reflectance of less than 0.3%), the multicoated UV filter blocks out ultraviolet rays ranging from 300nm to 410nm to reduce flare and ghosting while ensuring accurate color rendition | 【Strong Lens Frame】 Made of aluminum-magnesium alloy, the filter frame is strong and durable. With precision manufacturing and a matte black anodized finish, the screw-on filter is easy to use and has less reflections from the metal filter frame. The 0.22”/5.5mm thick filter measures only 0.13”/3.2mm in depth when screwed on your lens to avoid lens vignetting-ideal for wide-angle lens and telephoto lens | 【Super Slim & Non-Slip】 Super slim(only 0.13inch/3.2mm).non-slip design(trapezoidal pattern) ensure the friction is increased over a large area when rotate filter, very easy to install and remove the filter | 【Compatibility】 Compatible with all 49mm lenses. Please find out your camera’s lens thread size before buying. The thread size will be marked on the lens or the lens cap with the ‘ø’ followed by a number

【Softening effect】 The first and most obvious advantage of the white soft filter is its ability to soften and smooth out the image. This filter can help to reduce the harshness of the image, making it more pleasing to the eye. The softening effect can be particularly useful for portrait photography, as it can help to reduce the appearance of blemishes and wrinkles, while still maintaining a natural-looking image. | 【Creative effects:】The white soft filter can be used to create a range of creative effects. By experimenting with different settings and techniques, photographers can use the filter to create unique and interesting images that stand out from the crowd. Whether it's adding a dreamy, ethereal quality to a portrait or creating a soft and romantic mood in a landscape, the white soft filter can be a powerful creative tool for photographers of all levels. | 【Depth of field control】The white soft filter can also help to control the depth of field in the image. By softening the edges of the image, the filter can help to create a more shallow depth of field, which can be useful for creating a sense of depth and dimensionality in the image. | 【The HD optical filter glass 】Made from imported super white optical glass and combined with an excellent diffuse transmission manufacturing process, this product features a micron-level distribution texture that ensures uniform and diffuse lighting effects. | 【CNC Ultra Slim Threaded Frame】 Easy to screw to your camera lens through threads. The slim frame avoids unnecessary vignettes on wide angle lenses. Compatible with all 49mm lenses, please check your lens thread size before ordering (usually marked on the lens barrel or printed on the underside of the lens cap with a "ø"symbol.)

【Protective UV Filter】 This UV filter reduces haze and minimizes ultraviolet (UV) rays while improving contrast. Perfect for capturing high altitude and snow photos without the bluish cast. Keep this filter on your lens to protect against dust, scratches, and bumps | 【High-Quality Optical Glass】The quality optical glass protects your lens from dirt, scratches, fingerprints, and unexpected damage,Nano-Coatings Featuring 16 layers of optical coatings and a light transmittance of up to 99.4% (and a minimum light reflectance of less than 0.3%), the multicoated UV filter blocks out ultraviolet rays ranging from 300nm to 410nm to reduce flare and ghosting while ensuring accurate color rendition | 【Strong Lens Frame】 Made of aluminum-magnesium alloy, the filter frame is strong and durable. With precision manufacturing and a matte black anodized finish, the screw-on filter is easy to use and has less reflections from the metal filter frame. The 0.22”/5.5mm thick filter measures only 0.13”/3.2mm in depth when screwed on your lens to avoid lens vignetting-ideal for wide-angle lens and telephoto lens | 【Super Slim & Non-Slip】 Super slim(only 0.13inch/3.2mm).non-slip design(trapezoidal pattern) ensure the friction is increased over a large area when rotate filter, very easy to install and remove the filter | 【Compatibility】 Compatible with all 52mm lenses. Please find out your camera’s lens thread size before buying. The thread size will be marked on the lens or the lens cap with the ‘ø’ followed by a number

【Protective UV Filter】 This UV filter reduces haze and minimizes ultraviolet (UV) rays while improving contrast. Perfect for capturing high altitude and snow photos without the bluish cast. Keep this filter on your lens to protect against dust, scratches, and bumps | 【High-Quality Optical Glass】The quality optical glass protects your lens from dirt, scratches, fingerprints, and unexpected damage,Nano-Coatings Featuring 16 layers of optical coatings and a light transmittance of up to 99.4% (and a minimum light reflectance of less than 0.3%), the multicoated UV filter blocks out ultraviolet rays ranging from 300nm to 410nm to reduce flare and ghosting while ensuring accurate color rendition | 【Strong Lens Frame】 Made of aluminum-magnesium alloy, the filter frame is strong and durable. With precision manufacturing and a matte black anodized finish, the screw-on filter is easy to use and has less reflections from the metal filter frame. The 0.22”/5.5mm thick filter measures only 0.13”/3.2mm in depth when screwed on your lens to avoid lens vignetting-ideal for wide-angle lens and telephoto lens | 【Super Slim & Non-Slip】 Super slim(only 0.13inch/3.2mm).non-slip design(trapezoidal pattern) ensure the friction is increased over a large area when rotate filter, very easy to install and remove the filter | 【Compatibility】 Compatible with all 55mm lenses. Please find out your camera’s lens thread size before buying. The thread size will be marked on the lens or the lens cap with the ‘ø’ followed by a number