The Streamlight MicroStream USB is a compact, high-performance pocket light designed for durability and daily carry. It features a tail cap switch for momentary or constant-on operation and an aluminum alloy housing with Type II Military Spec anodizing for extreme abrasion resistance. The light offers amazing brightness for its size, delivering 250 lumens on high. Black Anodized Aluminum construction, OAL 3.87, Body Diameter 0.60, Weight 1.20 oz, Water Resistant, modes Constant / Momentary. This model includes an internal rechargeable Li-ion battery, USB charging cord, and a removable pocket/hat clip. To charge, simply slide the head cover forward to expose the port. It provides up to 3.5 hours of runtime on low.