A single-stage air compressor works by drawing air into the compressor’s cylinder, where it is then compressed with a single stroke of a piston and sent to a storage tank. This differs from a two-stage air compressor where, after the initial compression, the air is delivered to another high-pressure piston via a specially designed intercooler tube for a second compression. Depending on the model, a single stage air compressor can provide a pressure between 110 and 135 psi, while two-stage compressors can deliver up to 175 psi. Quincy Compressor’s Single Stage series is the perfect compressor for commercial applications and do it yourself (DIY) projects around the home or garage. Single Stage series compressors feature a cast iron cylinder, crankshaft and valve plate for strength and durability. The aluminum head and design of the fins help to dissipate heat to keep the compressor running as cool as possible for longer life. Single Stage piston compressors are 100% factory tested at full pressure and shipped with ISO-150, SAE 40 weight lubricant.