10-pack Car Humidifier Diffuser replacement sticks, Size: 2.75 inch * 0.31 inch; Color: White | Compatible for all car humidifier diffuser that are the same as the picture, like brand "nanum", can suit every humidifier like. | Usually 1 to 2 weeks, replace the filter, or easy to connect the machine. If you regularly use essential oils, need to replace 3 - 6 days. | Each Pack 10 filters under normal circumstances can be used for a long time. | Please Note: This filter is for nanum Car Humidifier Special