When the 5th Gen Camaro was released in 2009 as a 2010 the OE Upper Rear Control Arm Bushing was soft, very soft. We and other aftermarket suspension companies brought out a variety of solutions to stabilize the arms. When GM built the Z/28, they upgraded the bushing making it almost 4 time harder. They did the job so well it is the BEST solution for a 5th Gen Camaro used for drag, autocross road course or spirited street driving.
The JPSS kit includes a Left and Right genuine GM set of bushings. GM Part Numbers 23104906 and 23104907