The Mobilair M57 portable rotary screw compressor delivers 210 cfm at 100 psig and is designed for heavy-duty civil and commercial construction, demolition, sand blasting, and other site work applications as well as portable backup for stationary units. Features Sigma Profile rotary screw airend with direct drive produces more air with less horsepower Heavy-duty 4-cylinder diesel engine complies with Tier 2 EPA emissions standards Large fuel tank for extended operation High capacity cold start battery ensures reliable operation even under extreme working conditions Proprietary anti-frost thermostatic valve avoids tool freeze-ups Large tool box holds two 90 lb breakers