Volquartsen Assembled Lower Frame for Ruger Mark II, Mark III, 22/45 Target StyleA Complete Aluminum Lower Frame Replacement... Includes Volquartsen Accuracy System Internal Parts Our Volquartsen Custom Target Frame is CNC machined from aluminum alloy. Weighing only 7.1 oz, it is a complete frame with all internal parts including the Volquartsen Accuracy Kit: Extended Bolt Release, CNC machined Target Trigger, wire EDM cut Target Hammer and Target Sear, Titanium Disconnector, Built-in Spring Loaded Magazine Ejector and Extended Safety. Each Volquartsen Frame is shipped with a clean, crisp 2.25 lb trigger pull. And by popular request, the Mk III magazine disconnect has been eliminated. Fits Mk III Grips and Magazines - This is a complete frame. All you add to complete a gun is your Ruger Mk II, Mk III, or *22/45 upper (barrel, bolt, and mainspring housing), Mk III compatible grips, and a Mk III compatible magazine. *In order to use this frame on a 22/45 upper, a new Mk III mainspring housing, grips and magazine is required. Please note that this frame has the grip frame angle similar to the MKIII steel frame. If you need a mainspring to fit this frame, use the search box above to find and order the following: 140-MSR, 140-VC3MSR-3-B, or 140-VC3MSR-3-S Further Clarification: This frame does NOT accept 22/45 magazines. This frame does NOT fit 22/45 grips. This frame does NOT fit 22/45 mainspring housing.