Stainless steel compression tube fittings are durable, resist corrosion from caustic chemicals, corrosive fluids, oils, and gases, and withstand pressure and high temperatures. These metal fittings tighten with basic tools and can be used with multiple tubing materials. Hydraulic fittings are used with hydraulic fluids in hydraulic applications. Instrumentation fittings are made to tighter tolerances for high-precision applications.