Series 4703-4714 General Purpose Pressure Vessels, 22-45 mLThe Series 4703-4714 are the smallest of the Parr General Purpose Pressure Vessels. They have a 1-inch inside diameter and are offered in two different lengths with volumes of 22 and 45 mL.These vessels have a flat PTFE gasket that is sealed with a screw cap. Special wrenches and bench sockets are offered for tightening these closures. The screw caps and bodies are made of alloy steel for use at temperatures to 300 °C. The maximum working pressure is 1700 psi (115 bar).