The plastic ring that belongs on the inside of the housing which seals the unit and prevents leaking. O-rings should be lubed at each service. We do not recommend you remove the o-ring unless necessary, and avoid any stretching or alteration to the o-ring so that it will continue to fit properly. – PLEASE CONSIDER BUYING FOOD GRADE SILICONE LUBE FOR MAINTENANCE

AVAILABLE FOR 4.5” HOUSING

NOTE: NOT ALL O-RINGS FIT ALL HOUSINGS, O-RINGS SOLD BY PWF FIT ALL HOUSINGS SOLD BY PWF