For quick adjustability in any shooting situation, the 518 HWS offers multiple brightness settings in standard operating mode. | Mountable to a 1" Weaver or MIL-STD-1913 rail. | Powered by two 1.5 V AA batteries and supports lithium, alkaline, or rechargeable batteries. Lithium battery life: 2,500 continuous hours at nominal setting 12 at room temperature. Alkaline: 2,200 continuous hours at nominal setting 12 at room temperature. |