PPS-43 and PPS-43/52 welding jig. Made from aluminum so the weld will not stick to the jig itself, leaving you with a nice smooth inside weld. This also means its reusable and can be used 1000s of times. Fits perfectly inside the receiver and includes the slot to slide by the side detents.

The small diameter end is meant to fit into the trunnion, lining up the rear sight and barrel for best re-weld accuracy results.