A JP-5 lower uses its own magazine catch assembly, not the AR-15 part. When the catch wears, gets bent in a case, or a shooter wants to match the rest of the rifle’s controls, this is the factory replacement JP ships for the JP-5 lower receiver.
The reason most PCC shooters buy one is not failure. It is the fit with JP’s Enhanced Magazine Catch button, which threads onto this catch and gives the reload thumb a bigger target. JP builds the assembly in black plus four accent colors so the catch can match the button on the other side of the receiver.
One thing to know: this is the JP-5 part. It will not drop into a mil-spec AR-15 lower, and it is not an H&K MP5 part. It also ships as the catch assembly only, so a shooter who wants the extended button buys that separately.
The trade-off is price. Eighty dollars is a lot for a mag catch, but JP is the only source for this part and a worn catch on a PCC shows up as dropped magazines on the clock.