The high intensity 10-Watt Tektite Multifunction LED 3500 Strobe is double O-ring sealed, depth rated to { 500 ft | 152 m }, will run 100 hours on a set of three C-cell batteries and can also accept rechargeable Ni-Cad Batteries. The 3500 includes two eVDS factory programmed modes: a steady on mode for use as an emergency backup or area light plus the flashing on/off strobe mode. Visible at the surface for several miles/kilometers at night, the initial 1000 Lumen flash rate is 120 flashes per minute with fresh alkaline batteries. Features durable military tough ABS and LEXAN® construction, twist on switch with non-slip grip, safety orange color body with sturdy attachment point for snap or lanyard. At { 9.2 in | 23 cm } long and { 2.2 in | 5.6 cm } wide at the lens this strobe is too big to fit in most pockets. A { 15 in | 38.1 cm } Velcro strap is included, along with a limited LIFETIME Warranty from TekTite.