The R1 Concepts Geo-Carbon drilled-and-slotted rotor is provided as a single replacement for the front-right wheel of 2011-2016 Buick Regal models. The description lists a Geo-Carbon rotor with drilled and slotted surface treatment offered by R1 Concepts for the front-right position. This overview corresponds to the explicit Regal fitment and years noted in the product text and presents the rotor as the front-right unit for that application.
R1 11-16 Buick Regal Front Right Drilled & Slotted Geo-Carbon Rotor