Oil free, positive displacement rotary lobe blowers and screw compressor packages in pressure to 50 PSIG, capacities to 50 000 CFM. Low noise. Compact design. Frameless, weatherproof, sound attenuating enclosures. Aerators, Aerobic Treatment, Air Compressors, Blowers, Filter Equipment. Air and gas blowers for aeration, biogas and drinking water purification.