We actually tracked down the original company that manufactured the Colt® AR-15 optics of the 1970s and asked them to build a new one for us as close to the original as possible - right down the yellow inspection stickers. Like the Retro Rifles themselves, the Brownells Retro 4x Optic has updated technology under the hood. The result is a scope that looks just like the original but has optical clarity and performance that are head and shoulders above it. Fully Multicoated lenses are fog and waterproof BDC click-adjustable elevation turret Manufactured in Japan with high quality internals and lenses The Retro 4x Carry Handle Optic sports a simple, intuitive fine duplex reticle, like the original, and an elevation turret with BDC (ballistic drop compensated) clicks that closely match modern .223/5.56 55gr and 62gr ammo. As its name indicates, the Retro 4x comes with an integral carry handle mount that easily attaches to most AR-15 carry handles - no tools required. As with all products we sell, this scope is fully backed by our Forever Guarantee.