Why the weird input jacks on some EBMM guitars?

Went to put a new input jack in my BFR Luke (which is based off a Luke II) and noticed it is some weird plastic 4 prong piece of garbage. Cheap plastic parts on an input jack of a really expensive guitar? Asinine plastic stuff aside, what is up with the 4 prongs? Never seen anything like it. Only ever seen 3 prongs.