WABCO compressors significantly reduce power drainage during the off-load phase due to the PR (Power Reduction) system integrated into the cylinder head. They provide for lower temperatures of the delivered air from the temperature reduction (TR) system, which enhances the cooling capacity in the cylinder head. The (optional) relief valve integrated into the cylinder head provides protection against excessive pressure. WABCO compressors feature a proven design, including mono-block crankcase construction with excellent torsional resistance and a fully hardened steel crankshaft. Compressor service is extended and operation is maintenance free.