Black Hawk Serpa. I just purchased one, not for an H&K USP though. The Black Hawk for the USP fits the M&P C.O.R.E. PRO 9mm quite handily. I dislike the Black Hawk locking system but some seem to like it. I'll use it until I can find something that fits the C.O.R.E. I like better. A holstered pistol is a "safe" pistol so it's important.