Pentek OR-BB O-Ring

The rubber o-ring provides the water-tight seal between the cap and the bottom of the housing. The Pentek-OR-BB o-ring should be lubricated with clean silicone grease and placed in the groove below the threads of the housing to prevent a water leak. O-rings do not last forever and should be replaced any time you change the filter cartridge. The OR-BB is an inexpensive part of your filter system and helps protect you from water damage due to a leaky seal between the housing and cap. The Pentek O-Ring fits Pentek Big Blue housings. Replace your O-rings after every use to prevent leaks. Buna-N Replacement O-Ring.