The Vortex Optics 4-12X40mm Diamondback Tactical Riflescope is built around a 1" aluminum tube with high-quality, fully multicoated lenses tucked inside to deliver bright, clear images, even in low light. Intuitive and detailed holdover points on the Vortex Optics' 4-12X40mm Diamondback Tactical Riflescope, yet the lens remains uncluttered for optimum viewing. Exposed tactical turrets on the Vortex Optics 4-12X40mm Diamondback Tactical Riflescope allows shooter to quickly and precisely compensate for bullet drop and wind drift at extended ranges. A fast-focus eyepiece that sharpens the reticle image to suit the shooters eye. Second focal plane reticle Easy to r Mfg: Vortex Optics