Streamlight ProTac 2AA Pen Light Flashlight -The combination of small size and output from the C4 LED result in one of the brightest tactical personal carry lights for its size. The ProTac 2AA features a multi-function, rubber push-button tactical tail switch for easy one-handed operation of momentary, variable intensity or strobe modes. The TEN-TAP programmable switch allows the user to select one of three different programs: high/strobe/low (factory default), high only and lowithhigh. Market applications include, but are not limited to, law enforcement, security, emergency medical services, sporting goods, and personal use. C4 LED Technology, Impervious To Shock With A 50,000 Hour Lifetime Multi-Function, Push-Button Tactical Tailswitch. One Handed Operation Of Momentary, Variable Intensity Or Strobe Mode Anti-Roll Facecap, Removable Pocket Clip Length: 5.97 In (15.16 Cm) Major Diameter: 0.90 In. (2.29 Cm) Barrel Diameter: 0.65 In. (165 Cm) IPX7 Rated Design, Waterproof To 1 Meter For 30 Minutes.