SPECS: Machined 6061 T6 aluminum body, mil-spec hardcoat anodized, black. 100,000 hour LED service life. BD-198-HLS/BD-198-MH – 5" (12.7cm) long, 1-1/8" (2.9cm) diameter. 4.9 oz. (139g) wt. Uses two CR-123A batteries. BD-180-HLS – 3½" (8.9cm) long, 1-1/8" dia. 3.4 oz. (96g) wt. Uses one CR-123A battery. BDRC-HLS – 5¼" (13.3cm) long, 1-1/8" dia. 4.9 oz. (139g) wt.