RD7001
This is the speed sensor holder to be mounted over the speed sensor on the differential cover. It fits with the most BMW differentials pre-2000 which uses conventional speed sensor on the differential.
It is universal fit, no matter of diff size. Fits on E30, E34, E32...
Unlike the old differentials, it’s rust-free as it’s made of the aluminum. It’s anodized in different color options. Nice touch when you rebuild your differential.