Great for paddlers and recreational boaters, the Coast Guard approved UST Marine See Me 1.0 is a compact, steady on LED that emits 360deg of light visible up to 3.4 miles. Provides 20 lumens of light for 17 continuous hours on 2 AAA batteries alkaline or lithium. Unbreakable LED bulb never needs to be replaced. 3.4 mile visibility on a dark, clear night far exceeds USCG requirement minimum 1 nautical mile. Impact resistant and waterproof IPX7 rating. Easy to twist onoff. Can easily be attached to your PFD. Includes lanyard cord and Velcro strap. Dimensions: 4.95 x 1 in.. Weight: 1.8 oz..