196-5410, RS PRO, RS PRO Nitrile Rubber O-Ring O-Ring, 18.5mm Bore, 20.5mm Outer Diameter, Brand RS Pro, Type O-Ring, Material Nitrile Rubber, Inside Diameter 18.5mm RS PRO Nitrile Rubber O-Ring O-Ring, 18.5mm Bore, 20.5mm Outer Diameter