This part has been no longer available from BMW for over 20 years and I have recently had an OEM piece copied and printed using 3D printing technology. Here are the details:

Copy of BMW part # 52 10 1 875 827

The listing is for the control handle support only. No bolt, no knob, no bracket.

Cosmetically not perfect, but I am trying to keep costs down, and the cost of this piece goes way up if it is smoothed and made to look pretty. Since a control knob fits over it, the aesthetics are not very important.

The unit is constructed of ABS plastic and fits tightly to control shaft, and the control handle fits snugly to the support piece offered in this listing.

Each seat requires 1 control knob and support, so if you need 2 of them, select 2.

If you want a control handle, you can order one from Aardvarc here.