The original Chemtrol True Union design allows the valve and operational components to be conveniently lifted from the piping system for repair or replacement. Tru-Bloc advances the True Union concept with the self-adjusting energizer O-ring. The valve can be easily joined with the socket end connections. 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. Chem-Pure natural polypropylene demonstrates excellent chemical resistance properties, including aqueous solutions of acids, alkalis and salts, and a number of organic solvents. Choose Chemtrol valves for the most reliable, versatile and economical valve option in commercial and industrial applications. Chemtrol ball check valves are backed by a 1-year limited warranty. Because Chemtrol is a NIBCO brand the flow-control valves are unsurpassed in quality, performance and longevity.