Nikon M-223 BDC 600 8487 2-8x32 Riflescope (Black) Riflescope for AR rifles delivers extreme speed, accuracy, and shooting confidence BDC 600 reticle offers shooters unique open circle aiming points and hash marks from 100 to 600 yards 32mm objective diameter, 2x to 8x magnification, 4 inches of eye relief Nitrogen-filled and O-ring sealed for protection against water, shock, and fog; multi-coated optics Backed by Nikon's full lifetime warranty