Oil-less BREATHING Air Direct Drive Compressor Sealed Stainless Steel Compressor Bearings with Breathing-Air/Oxygen compatible grease are the hallmark of our proprietary diver specific compressor. The complete main bearing and eccentric crank assembly are machined from high-quality stainless steel. Even our reed-valves are made in America by a very precise etching method and are pure high-grade stainless. NOTE about copycats: Construction compressors (Thomas and others) utilize traditional uncoated aluminum, painted metal parts and iron/steel crank eccentric materials with typical industrial grade petroleum greased bearings. Since 1969, Brownie’s has lead the way in developing the ultimate THIRD LUNG, and our precise compressor assembly is at the core of that achievement. Our intentionally low RPM compressor speed equals longer life, less noise, lower heat factors and all around more pleasant diving than high-speed low-cost air compressors.