We manufacture this superior quality valves ( Model 1220 ) to work under extreme conditions. These are designed specially to vent low pressure vessels. Operating conditions like temperature and corrosive atmospheres help determine the material combination to be used in making these valves. These range of valves are available using pure aluminum, cast steel, stainless steel or cast and body, stainless steel trim, brass, teflon. They can also be made from other materials on special order.