Named in memory of former Sightmark colleague Caleb John Richard Koszewski, the Sightmark® CJRK Riflescope QD Mount combines a rock-solid platform for mounting high-power riflescopes on flat-top rails with the versatility of a quick-detach tactical mount. Shooters can easily configure the CJRK Riflescope QD Mount's lever to lock to the front or the rear, depending on their preference. The CJRK Mount's dual lever attachment grabs the picatinny or weaver-style rail in two places, preventing from unwanted movement or shifting, and allowing the user to remove and replace their riflescope as desired without loss of zero. Its quick-release lever-lock system clamps solidly to a flattop rail and will not loosen even under heavy recoil. The cantilever design gives plenty of room to achieve both accurate eye relief and height above the riser on all riflescopes with a 4-inch or less eye relief, preventing the need to span between the riser and quad rail. Simply lift up the release tab to swing the lever open, and the mount easily lifts off the rifle. Six heavy duty steel hex screws (3 on both sides) clamp the horizontally split ring halves together, providing exceptional durability. Engineered from aircraft-grade aluminum, the CJRK Riflescope QD Mount is extraordinarily lightweight at only 8 oz., allowing for a comfortable, lighter lift and the ability to apply additional accessories to the Firearm if needed.