Crimp hose fittings join hydraulic hoses to compatible NPSM (National Pipe Straight Mechanical) threaded equipment or hoses. They are commonly used in hydraulic applications with petroleum-based fluids and lubricating oils. They have a crimped end that attaches to hydraulic hoses and an NPSM threaded end that attaches to equipment. The NPSM connection forms a tight seal when mated with the opposite gender. A crimping device seals the fitting for a permanent connection. These fittings are made of steel for strength, durability, and wear-resistance in high-pressure applications, or carbon steel that is hard and resilient, but more susceptible to corrosion unless alloyed with other metals for resistance.