Always the correct part
Beach RC says...
TKR6780 – Shock Cap Bushings (requires TKR6527B, EB/ET410, 4pcs)
Increase the life of your shock caps with these new shock bushings! They are designed to snap in and key with the top surface, making it virtually impossible for the bushing to rotate and wear the cap. Instead, the wear surface has been moved to the shock bushing itself reducing the cost to maintain your suspension.