solid disc ATE with 239mm discs
LH - 1H0 615 123 C
RH - 1H0 615 124C
vented disc GIRLING 256mm discs
LH - 357 615 123 AX
RH - 357 615 124 AX
vented disc GIRLING 280mm
uses same as 256 above as above but the mounting frames are different
solid type fits straight to the hub but the vented ones need a frame that bolts on as well but if you are planning to fit bigger vented discs/calipers you will need frames calipers and a hub each side also
what setup do you have and what are you planning to do ?