The EOTech HWS 518 delivers all the advantages of the popular EOTech HWS 512 and EXPS models, respectively, in one tough unit. With long-run life using easy-to-find AA batteries, the quick-detach lever and side control functionality allows for mounting our EOTech G33 Magnifier behind the sight. NON NIGHT VISION COMPATIBLE L X W X H 5.6” x 2” x 2.5” (143 x 51 x 64 mm) WEIGHT 11.5 oz (325 g) WATER-RESISTANT 10 ft. (3 m) depth MOUNT 1” Weaver or MIL-STD-1913 rail BRIGHTNESS 20 daylight settings POWER SOURCE 2 x 1.5 V AA batteriesSupports CR123, alkaline, or rechargeable BATTERY LIFE CR123: 2,500 continuous hours at nominal setting 12 at room temperature.Alkaline: 2,200 continuous hours at nominal setting 12 at room temperature. COUNTRY OF ORIGIN Made in USA