Streamlight Polytac LED Hp BlackThe Streamlight Polytac LED HP Black has C4 LED technology with a 50,000 hour lifetime. The lens is made of unbreakable polycarbonate with scratch resistant coating. There are 3 hours of continuous runtime to the 10 percent output level. 50,000 hour lifetime Borofloat glass lens, o ring sealed Tail cap push button provides one handed momentary or constant "on" 3 hours of continuous runtime to the 10 Percent output level Two (2) 3 Volt CR123A lithium