Colt 1" one piece scope mount with extended base. Designed to mount scope with a 1" main tube to your Modern Sporting Rifle with a flat top receiver. CNC Machined from solid 6000 Series Aluminum Alloy stock. Torque specs: 1/2" rail clamp nuts - 65 in-lbs. 8-32 Ring Screws - 25 in-lbs.