LED & Modes -- The K1 mini flashlight uses a super bright LED and has 3 modes: High, Low, and Strobe. | Power Source -- Runs on all types of AAA battery. Since it's economical and readily accessible, you can use AAA Alkaline battery, AAA Ni-MH battery, or 10440 Li-ion rechargeable battery for K1 keychain flashlight. | Versatile Applications -- EDC, law enforcement, security, emergency, medical services, camping, duty light, and self-defense. | High Quality -- Constructed from aerospace-grade aluminum body with the military-grade hard-anodized anti-abrasive finish. | Compact and Lightweight: The dimension is 2.95 x 0.59 in, and is only 0.49 oz, making this super bright flashlight convenient to be taken anywhere.