Due to the change in the Gen 2 trailing arms, these stainless steel conical washers allow you to fit Gen 1 coilovers onto your Gen 2 or JCW GP MINI. This 'fills the void' between the R53 rear strut and R56 trailing arm, due to the R56 strut / shock having a built in bushing at the base of the strut, which extends into the trailing arm.
These are also required if you've upgraded your Gen 1 trailing arms to the lighter Gen 2 alloy trailing arms.
These conical washers allow you to fit Gen 1 coilovers onto your Gen 2 or JCW GP MINI, or if you've upgraded your Gen 1 trailing arms to the lighter Gen 2 alloy trailing arms, and are supplied in pairs (2).