The Ridgid 4-1/2-Gallon Portable Electric Air Compressor features a 1.8 HP engine. It has an oil-free, low-maintenance pump with thick cylinder walls that delivers air power and has a long life. This air compressor delivers 4.9 SCFM at 90 psi, which means that 2 nailers can be used simultaneously. The durable tanks are made of steel. Manufactured by the leader in air compressors Campbell Hausfeld.