SCHUMAK two stage air compressor is the best energy efficient piston air compressors. These two stage air compressor incorporates simple back-pressure relief valve for reducing initial torque on the motor. Crankshaft, connecting rod, cylinder, valve, and piston are specially designed for 2 stage air compressor . Cylinders are made from special cast iron material with deep radial fins on the outer side for quick heat dissipation. Each cylinder is separately cast, precision-bored and honed for smooth running. The main advantage of these two stage air compressor is low specific power consumption and long service life.