Atlas Copco Compressor Sales offers Oil-Free Piston Compressors. Atlas Copco Compressor Sales is an ISO 9001 and 14001 registered organization. The Oil-Free Piston Compressors are high-performance and long-lifetime small capacity compressors providing 100 % oil-free operation. The capacities ranges from 1.02 to 2.53 l/s [2.16 - 5.36 cfm] with options for 1- or 3-phase supply and with a maximum working pressure of 10 bar [145 psi].