3 1/2" overall. CREE XP-G R5 LED. Turbo mode with 280 lumen output and 1 hour, 15 minute runtime. Four customizable modes: strobe; low - 20 lumen output with 23 hour runtime; medium - 60 lumen output with 8 hour runtime; and high - 125 lumen output with 3 hour, 15 minute runtime. 115m beam distance. Uses one CR123 battery. Includes detachable pocket clip, black cord wrist lanyard, spare plastic cap, and spare O-ring.