It does just what the name says, Primary Case Protector. It slides right into your primary case and bolts in to the hole already there, with one bolt. It serves as a buffer between your chain and cases. This will stop chain slap from putting grooves in your cases and eventually ruining them.
I attached a couple of pics., the first one is an installed pic. The angle faces down toward the chain and is facing the rear sprocket. This is designed to work as a lead in for the chain into the primary case and will protect cases from chain slap. The second one is what you can expect it to look like after it starts doing it’s job. The outer edges will wear the UHMW until the rollers on the chain hit. Once the rollers take over the wear stabilizes and your cases are now protected:) The one in the pic has been on my bike for over 2 years.
Note: Some year cases do not have hole and you have to drill your own.
$15.00 Shipped Cont. USA