PTFE valve stem packing is a self forming packing material. It forms to all surface irregularities such as scratches and pits. It is made from 100% virgin PTFE and has a high tensile strength. It is self lubricating and eliminates valve stem wear. It contains no contaminates and is unaffected by most common chemicals. The temperature range is -450F to +550F. It is easy to stock due to its unlimited shelf life. For use on valves, faucet stems, rotating shafts, reciprocating plungers, and flanges. We also offer a graphite valve stem packing. This material has graphite mixed in with the PTFE as an additional lubricant. It holds all the same properties and temperature ranges as the PTFE valve stem packing.