Automatic/ Manual Activation; Manual Deactivation; Automatically Activates When Immersed In Water And With Manual Push Button Boasts 20 Lumen LED; Steady On Light; 120 Hours Operational Life; 1.38 Inch Width x 1.2 Inch Depth x 5.56 Inch Height; Waterproof Up To 1 Meter For 24 Hours; USCG/ SOLAS/ CE/ Transport Canada Certified; With PFD Clip/ Lanyard/ Velcro Strap; Carded; Works With 2 AA Batteries(Sold Separately)