Polaris RZR Pro R Rear Chassis Clamp (Bung). Machined from billet to very close tolerances. Machined to mount off stock chassis clamp to 1.75" tubing. These are used on the B-Pillar and C-Pillar on the 2 Seat Pro R and used on the C-Pillar and D-Pillar on the 4 Seat Pro R (rear bungs).