When dusk arrives and danger lurks, you need a compact holographic weapon sight like the EOTech XPS2 Zombie Stopper Holographic Weapon Sight. From brilliant to low glow, the biohazard symbol and dot deliver quick and deadly target acquisitions in 20 different brightness settings. Integral mount secures to Picatinny or Weaver-style rails. Waterproof and fogproof. Runs on one CR-123 battery (not included) for up to 600 hours. Dimensions: 3.75"L x 2.4"W x 2.4"H. Weight: 8.8 oz.