Originally Posted by Emil
S4007 is engraved on the pads, so I can confirm this. But these seem to be BMW-exclusive, I could not find them elsewhere. Maybe you have more luck or better sources
Indeed, these pads are also referred to as "S4007" by bmwfans.info
. I've found two vendors who can source them, though they are pricey.
I dug into those PNs a little further, and according to Real OEM, the front sport pads are only to be used in conjunction with rotor numbers 34112283385 and 34112283386, which are the stock rotors that come on our cars. So far so good.
However, the rear sport pads are only to be used in conjunction with rotor numbers 34212283387 and 34212283388, which are different than the PNs for the rear rotors on our cars. The PNs for our rear rotors are 34112283801 and 34112283802.
Do you happen to know what the difference between xxx387/388 and xxx801/802 might be?