Specification BatteriesRequired : 1 Brand : APEC WATER BulletPoint1 : IMPORTANT: A set of 3 o-rings for standard filter housings of APEC ESSENCE reverse osmosis systems purchased BEFORE JUNE, 2013 and ULTIMATE reverse osmosis systems purchased before MAY, 2015 BulletPoint2 : Diameter 3.5" OD. BulletPoint3 : Light Weight,Easy Install and Unload BulletPoint4 : Manufactured using NSF-compliant materials BulletPoint5 : Pack of 7. 1 x Filter housing , 2 x O rings ,1 x wrench,2 x fittings,1 set screws BulletPoint6 : Fit with 80% (NOT ALL ) RO systems using STANDARD 10" filters.But different brand,the injection mould is totally different,NOTE:PLEASE REPLACE HEAD AND HOUSING BODY TOGETHER.,IF OTHER BRAND,IT MAY DON'T FIT,if you mind to replace old top head,please replace housing with old brand BulletPoint7 : If you need 10 inch whole house water filter housing, inlet and outlet should be 3/4 inch ,please refer our other product ASIN B07LCKBKCT | B07LCKLP5K | B09WDBBTZV via Amazon Color : black ExternallyAssignedProductIdentifier1 : 854961005969 ExternallyAssignedProductIdentifier2 : 0854961005969 ExternallyAssignedProductIdentifier3 : 00854961005969 ItemDisplayDimensions_Height : 4.7 inches ItemDisplayDimensions_Length : 11.6 inches ItemDisplayDimensions_Width : 4.7 inches ItemDisplayWeight : 2.2 pounds ItemLength : 192 inches ItemName : APEC Replacement ORing for ROES-50 3.5" OD Reverse Osmosis Water Filter Housings, O-Ring (3 pcs O-RING-SET-A) ItemPackageDimensions_Height : 17.2 centimeters ItemPackageDimensions_Length : 0.7 centimeters ItemPackageDimensions_Width : 8.8 centimeters ItemPackageQuantity : 1 ItemShape : Round ItemTypeKeyword : undersink-water-filtration-system-replacement-parts Manufacturer : APEC WATER SYSTEMS Material : Rubber ModelName : RO5-FH10S ModelNumber : O-RING-SET NumberOfItems : 1 PartNumber : O-RING-SET Pattern : Version A ProductBenefit : Clear housing is convenient to indicate and track of your filter life .It is time to replace a new one when you find PP sediment is dark yellow or brown color ProductDescription : Operation Specification: FEED WATER PRESSURE :35 - 100 PSI TEMPERATE: 40 - 110°F/5-45°C PH :3.0 -11.0 MAX TDS 1000 MG/L TURBIDITY < 1.0 NTU MAX SDI <4.0 HARDNESS < 5 GPG IRON <0.1 Life time :3 years Shelf life: 5 years in original sealed package.