This is a set of rear trailing arms for your Alpha platform/chassis '13+ ATS coupe/sedan/ which includes the V. They are made of .120 tubular steel and have solid polyurethane bushings, far superior to the factory pressed sheet-metal arms with rubber bushings. There are 3 bars per side, so this complete set will include 6 total bars. The install should take less than two hours.
These are the same arms that are installed in Turbo Tim's ATSV that runs in the Gridlife road course racing series. They are a huge improvement over stock. Far more stable in the rear around corners and straight line acceleration. *Note: may also fit CTS-V sport.