Parts according to Knight's terminology:
Hammer, End Cap, Secondary Safety, Hammer Screw.
Spring is missing in this picture of a disassembled hammer assembly.
I talked to Sam at Knight a few years ago when I disassembled one for the first time. He was the one who advised me to use some heat and be very careful not to twist that leetle screw off.
You can see how this End Cap is marred from some jass ack putting an unpadded pliars on there.
Art