This is an insert that fits into voids in the original bushing to reduce subframe movement.

This part fits the following models:
BMW
2 Series
F22 2 Series Coupe RWD (2014+)
F22 2 Series Coupe xDrive AWD (2014+)
3 Series
F30 3-Series RWD (2012+)
F30 3-Series Xi AWD (2012+)
4 Series
F32 4-Series RWD (2014+)
F32 4-Series Xi AWD (2014+)