The Chemtrol thread cap features a female NPT thread connection and is used to seal off the end of piping. Chemtrol fittings are lightweight, easy to install and maintenance-free. Please refer to Chemtrol technical data sheets, chemical resistance guides and catalogs for engineering and installation information. Chemtrol® Chem-Pure® polypropylene exhibits extremely low content of metals, organic compounds, and free ions. No pigments or other adulterants (natural) are added to the plastic resin.more Chem-Pure® natural polypropylene demonstrates excellent chemical resistance properties, including aqueous solutions of acids, alkalis and salts, and a number of organic solvents. Chemtrol® premium line of plastic fittings are backed by a 1-year limited warranty. Because Chemtrol® is a NIBCO brand the flow-control fittings are unsurpassed in quality, performance and longevity. less