The ProTac Flashlight is crafted of machined aircraft aluminum with an anodized finish. It is constructed with tempered glass and O-ring sealed for water resistance. The C4 LED technology is impervious to shock with a 50,000-hours lifetime. It is equipped with a multi-function, push-button tactical tail switch which allows 1-handed operation of momentary, variable intensity. Requires 1 AA battery (included) or strobe mode.