PETZL - ULTRA RUSH BELT Headlamp, 760 Lumens, Constant Lighting, with ACCU 4 Battery ULTRA POWERFUL UNIFORM LONG-DISTANCE LIGHTING: Uniform lighting up to 760 lumens and beam up to 170 meters. CONSTANT LIGHTING: performance does not decrease as the batteries are drained; then switches to reserve mode. HIGH CAPACITY ACCU 4 BATTERY: ACCU 4 ULTRA Lithium-Ion remote rechargeable battery (5200 mAh) offers maximum burn time while reducing weight on the head EASY TO USE: Rotating selector knob is easy to use, even with gloves, allowing rapid access to different modes. RUGGED: Waterproof to -1 meter for 30 minutes. Excellent resistance to falls, impacts and crushing.