CaseyRyback· Premium Member
I just found this out the hard way.There are two types, the old type with the short catch and the new type with the long catch.
For pistols 2005 and newer you'll need hammer part # 215870, pre-2005 hammer part # 214825. You can use the older hammer in a newer pistol if you swap out the Catch, part # 214773.
In my USP manual, and the one I downloaded form HK-USA's FAQ page, lists the part number as 214825 so thats the part I ordered. It turns out that the manual is wrong and out of date. Thanks HK.