KleenWater Brand Water Filter Housing Replacement O-Ring for Cuno Aqua-Pure AP200 / AP217

KleenWater Brand Water Filter Housing Replacement O-Ring for Cuno Aqua-Pure AP217. Replacement o-ring for 3M Purification Cuno Model AP200. We recommend consumers keep a spare o ring on hand to avoid urgent situations. An o ring facilitates a water tight seal between the water filter sump and the water filter head. The most common o rings (o-rings) used in water filtration are made from Buna N material. Buna N is also commonly referred to as nitrile. This is the ideal choice for cold water filtration because they are inexpensive and have superior performance characteristics. KleenWater is a trademark of Pavel Water Filtration.