Select a Product Part NumberIncludesUsed on 2180RK1515 PSI spring (+2/-0 PSI tolerance), spring seat, diaphragm, valve plate, bolts, lockwashers, tamper proof seal and valve label2180/15 2180RK1818 PSI spring (+2/-0 PSI tolerance), spring seat, diaphragm, valve plate, bolts, lockwashers, tamper proof seal and valve label2180/18