This is a 90A Bosch Alternator for the BMW Z3 and 318i. This Is a Similar Unit to the Valeo 13664 (80A). This Unit Uses 2 Top and 2 Bottom Mounts Like the 13381, etc, and a 6-Groove Serpentine Pulley. The Rear Plastic Cover is Round, as are Most Bosch Internal Fan Units, Except Here Where the Battery Terminal Hookup is (9:00) There is an Extra Triangular Molding in the Cover. Both the B+ and the D+ Appear to Be Housed Here. The 13619 (70A) is Also Used on BMW, and Looks Very Similar to the 13733, Except the Adjusting Ear Thickness is Different, They Use Different Pulleys, and the Rear Covers Are Slightly Different.