LED technology with four lighting modes; High for a super-bright beam that pierces through smoke: 175 lumens; 405m beam distance; runs 4 hours; Low for bright light and longer run time: 60 lumens; 237m beam distance; runs 15 hours; Flash for signaling: runs 8 hours; Moonlight mode provides low-level lighting for battery conservation: runs 20 days; A low-profile bezel that doesn't interfere with gear and equipment; The clip securely grabs onto gear; Rubber dome push-button switch provides easy operation even when wearing heavy gloves; The reinforced D-ring allows the light to hang forward consistently; Optimized electronics provide regulated intensity; High-impact super-tough nylon construction offers exceptional durability; O-ring sealed, unbreakable polycarbonate lens with silicone anti-scratch coating is assembled in a heavy-duty bezel; Accepts four (4) AA alkaline batteries