KYB Rear Strut Boots Jounce Bumper and Bellows | BMW 320 Series (77-83) / Volkswagen Jetta (80-84) / Volkswagen Rabbit (80-84) (SB113)

You only need to order these if the boot / bumpstops on your car are missing, worn out, or need replacing.

Normaly, your original boot / bumpstops are simply reused. But you do have to remove them while changing out a unit, so while you are there already doing the work, it's easy to just slip the new parts on since you already have the car apart.