3/4" Temperature and Pressure Relief 150 PSIGThis Apollo automatic temperature and pressure relief valve features a unique non metallic coating which protects the element against galvanic and electromechanical corrosion by isolating it from the heated water. This coating is electrostatically applied for uniform coverage, then thermobonded, resulting in optimum adhesion for extended service life. CSA design certified at all settings to ANSI Z21. 22. ASME Section IV rated at 125 psig and 150 psig