Suttner Safety Pressure Relief Valves - Pressure Wash AccessoriesSuttner ST-230 Safety Pressure Relief Valves 250 & 350 bar. Adjustable pressure, forged brass housing, stainless steel ball and valve seat. Special seals for maximum heat and chemical resistance. Valve member rides on elastomeric cushion, eliminating metal to metal contact, a common cause of regulator failure. Quickly rebuildable with repair kit. Can be rebuilt without removing from the installation. EPDM oring