Nikon M-223 2.5-10x40 Laser IRT Black Matte Riflescope (BDC 600) Precise riflescope with 2.5 to 10x magnification and 40mm objective lens Immediate Ranging Technology ranges and displays distance to target for 12 seconds BDC 600 reticle gives shooters unique open circle aiming points from 100 to 600 yards Generous 3.5 inches of eye relief; Ultra ClearCoat optical system for image clarity Zero-reset turret; low-profile mounting system; measures 12.3 inches