2011-2022 Chevrolet/GMC 2500/3500HD RWD, 4WD 2'' Rear Block Kit for use with Factory Top Overloads Injectors 2010-2012 Cummins 6.7L spring loaded cylinder and pressure

spring loaded cylinder and pressure regulation provides up to 150 retarding horsepower throughout the engine's RPM range - not just at high rpm like some designs that use holes or additional parts and claim it as a better idea

Shoulder grooves are arranged in alternating widths and lengths to clear mud and maintain traction

Bump stop mount extensions

With this kit installed

2011-2022 Chevrolet/GMC 2500/3500HD RWD, 4WD 2'' Rear Block Kit for use with Factory Top Overloads Injectors 2010-2012 Cummins 6.7L spring loaded cylinder and pressure2 inch rear lift 2 & 4WD 2500HD single rear wheel with factory trailer package springs 3500HD dually OEM style cast iron construction Kit includes: pair of rear lift blocks Extended U bolts and hardware