Available in 316 Stainless Steel, Monel, Hastalloy, Inconel, and more, HART Industrial spiral wound gasket unions provide Class 3000 Service in extreme temperature and environmental conditions. Flat face design provide turbulence-free fit across seats. While standard graphite spiral wound gasket union is resistant to 850°F and suited for hydrocarbon and superheated steam service, optional silicate spiral wound gasket union is resistant to 1,850°F for superheated and chemical service.