The Wheeler MSR Cantilever 1 Piece mount is a 6-hole tactical 1 piece rings with integrated anti-cant indicator. This mount is perfect for adding your favorite scope to the AR-15 platform. The 2" extension allows the shooter to mount the scope at a comfortable distance for proper eye relief. The swing out anti-cant level helps keep the reticle level while shooting at distance. Features:6061 aluminum construction with flat top ring2" cantilever extension6-hole ring design with retained 1/2" lock nuts that secures to the picatinny railSwing out anti-cant levelIncludes torx screws Note: The outside-to-outside measurement is 125mm (4.92") and the inside-to-inside measurement is 75mm (2.95"). The thickness of each ring segment is 25mm (0.98")