Model 512 is our most popular holographic weapon sight. It's ideal when you need the best in speed and versatility, without night vision compatibility.FEATURES: Submersible to 10 ft. (3 m) depth; 1 Weaver or MIL-STD-1913 rail mount; Two 1.5 V AA batteries Supports lithium, alkaline, or rechargeable; Lithium Battery Life: 1,000 continuous hours at nominal setting 12 at room temp.