JACO polypropylene fittings are lightweight, rigid, resistant to environmental stress cracking, and have a good chemical resistance. JACO PP fittings are an opaque flat white color and are 20% glass-filled for improved strength. Polypropylene is unaffected by alkalis (bases), salts, most weak acids and has good resistance to organic solvents when used in temperatures below 175° F. It is not suitable for oxidants, strong acids, chlorinated hydrocarbons, high concentrations of free chlorine, and aromatic compounds (such as benzene and toluene). JACO polypropylene fittings are often used for high purity applications such as deionized water. Avoid using JACO polypropylene fittings in continuous sunlight.