The Urethane Supply Company Nitrocell nitrogen welder, No. 6066-CG, is designed to generate its own nitrogen gas from shop air and requires no onboard air compressor, according to the company. It features an easy-to-handle welding torch, and the 6066-CG Nitrocell employs a three-stage filter to clean impurities from the air, and then uses sophisticated membrane technology to extract a supply of nitrogen. Its analog instrumentation features a control regulator combined with an output pressure gauge and a flow gauge to give the operator total control over the amount of gas used in the welding process. A low-pressure safety switch automatically cuts power to the heating element, protecting it from overheating if the flow drops too low.