New in box Polymer80 - PF45 Frame Frame Kit is everything you need to start your large frame size Glock 10mm (G20SF), .45 ACP (G21SF).  The Polymer80 - PF45 frame kit includes the 80% large pistol frame, jig, and all tooling required to finish the frame using a drill press and XY cross-vise. Flat dark earth.  Features like the extended beaver tail, double undercut trigger guard, and a thumb ledge considerably enhance the ergonomics allowing for an effective grip and improved recoil mitigation.