QD Scope Mounts Midwest Industries incorporates on of the smoothest functioning QD levers on the market. Extremely smooth in operation with a multi-facetted adjustment nut to get the exact tension required without damaging the rail surface. Fully adjustable with no tools. Weighing in at 8.4 oz, these mounts are precision machined for optimum return to zero performance and reliability. Hard coat anodized 6061 Aluminum for a lifetime of service. Works with scopes up to a56mm objective lens. Works with scopes up to a 56mm Objective Weight: 8.4 oz Overall Length: 5.875" Width of Rings: .85" Distance between rings: 2.8" Offse Mfg: Midwest Industries