For those using coilover springs in the rear of their E36/E46, these are designed to align the spring so that they can use a lower rear adjuster. If your suspension is using a rear spring between 5″-5.5″ long, the spring can actually fall out of the spring pocket at full droop (when on a lift or on jack stands). These perches line up the tapered end so that they do not come fully unseated.
These are available in black (for 60mm/2.25″ ID springs) or white (for 2.5″ ID springs). Sold as a pair.
These do NOT fit OE style replacement springs (such as H&R, Eibach, Dinan, etc.) They also do not fit the rear springs included with Bilstien PSS/PSS9/PSS10 or any KW/ST kits.