The R1 Concepts Geo-Carbon drilled-and-slotted rotor is provided as a single replacement for the rear-right wheel of 2011-2016 Buick Regal models. Described in the source as a Geo-Carbon rotor with drilled and slotted braking surfaces, this R1 Concepts item is supplied for the rear right position. The overview aligns with the Regal fitment and years cited and presents the rotor as the rear-right replacement for that application.
R1 11-16 Buick Regal Rear Right Drilled & Slotted Geo-Carbon Rotor