Rear axle stub nut (collar nut), M24x1.5, multi-point retaining nut that holds the rear axle into the hub.
This is a Genuine BMW axle nut with a two year warranty. Buying a Genuine part will usually be more expensive than an OEM or aftermarket brand but you are assured that it meets BMW's designs for fitment, performance, and longevity. It will also be the very latest design, incorporating any updates or revisions that an aftermarket brand typically will ignore.
BMW Fitments:
1 Series
E82 / E88 (08-13) > 128i
3 Series
E36 (92-99) > 318i M42
E36 (92-99) > 318i M44
E36 (92-99) > 318ic M42
E36 (92-99) > 318ic M44
E36 (92-99) > 318is M42
E36 (92-99) > 318is M44
E36 (92-99) > 323ic
E36 (92-99) > 323is
E36 (92-99) > 325i
E36 (92-99) > 325ic
E36 (92-99) > 325is
E36 (92-99) > 328i
E36 (92-99) > 328ic
E36 (92-99) > 328is
3 Series
E46 (99-05) > 323Ci
E46 (99-05) > 323i
E46 (99-05) > 325Ci
E46 (99-05) > 325i
E46 (99-05) > 328Ci
E46 (99-05) > 328i
3 Series
E90 / E91 / E92 / E93 (06-13) > 323i
E90 / E91 / E92 / E93 (06-13) > 325i
E90 / E91 / E92 / E93 (06-13) > 328i
Z Series
E85 / E86 Z4 (03-08) > Z4 2.5i M54
E85 / E86 Z4 (03-08) > Z4 3.0i M54
E85 / E86 Z4 (03-08) > Z4 3.0i N52
E85 / E86 Z4 (03-08) > Z4 3.0si N52
Z Series
E89 Z4 (2009-2016) > Z4 sDrive28i
E89 Z4 (2009-2016) > Z4 sDrive30i
E89 Z4 (2009-2016) > Z4 sDrive35i
E89 Z4 (2009-2016) > Z4 sDrive35is