Don't be fooled by o-rings made of inferior compounds, this Pool Ruler o-ring is made from OEM spec Viton (FKM) which is chlorine resistant and will last up to 4 times as long as generic o-rings. We back our product with a full season guarntee. If your o-ring fails, swells, or has a problem, contact...

This cap o-ring is designed to use with Pentair standard and high square feet module cartridge filters and also compatible with Pentair Rainbow automatic chlorine/bromine pool and spa feeder model 300, 302, 300-29X, 320, 322. Also fits Pentair Rainbow automatic chlorine/bromine feeder extensions.

2 Pack Aftermarket O-Ring Replacement For Pentair Rainbow 300/320 Chlorinator Lid R172009 O-283

Quality Replacement Parts by Professor Foam which fits the Model numbers: 300 and 320.