This is an 80A Valeo Alternator for BMW. The Bosch 13465 May Also Fit Here. The Rear Bottom Mounting Hole is Unthreaded. This is the Earlier Version of the 13470. The Bottom Mounting Hole on This Version is Unthreaded (The Nut is Seperate and Attached Behind the Rear Mounting Hole). A Hex Mounting Bolt (Size M10 x 1.5), Washer, and Nut Could Be Included in the Box With the Unit (If Supplying a Unit Without the Threaded Bottom Bushing) to Replace the Later Unit With the Threaded Bushing. It Appears That BMW May Have Gone to the Threaded Bushing Because of Heavy Rust Build-Up and Corrosion on the Unthreaded Unit Rear Mounting Area (With Seperate Nut), This is What Rebuilders Report They See on the Cores Being Returned.