Wheel cylinder - 1", Raybestos, RH, for GT350 brake kit. We are a believer in larger wheel cylinders. Standard size wheel cylinders are not large enough to have sufficient force for severe braking conditions. Larger wheel cylinders will increase the ability to apply more pressure to the shoes and drums. We recommend a 1” wheel cylinder on 10” brakes under most conditions. A great upgrade for the street as well. We also recommend our larger master cylinder to compliment the need for more fluid volume with larger wheel cylinders. All wheel cylinders universally fit either brake size.