H&k usp rail adapter- worth the $10 - LaserLyte Heckler & Koch USP Rail Adapter Black ADP-HKSP-140

Its cheap, but it works. Comes in two pieces that screw together. The bottom has shallow holes on one side and the other side has little nubs that fit into them. The holes are not deep/wide enough to fit, so I had to drill mine out a little in order to get it to go together flush. For $10, its worth it regardless. I wasn't paying $60 for a rail adapter, and this worked out perfect for me despite the cheaper shortcomings. It was what I expected and I'm satisfied with it.
Pros: Cheap
Cons: Cheap

This review was written in the old system and had content requirements that are different than reviews written today.