Specification Brand : WFCYQ BulletPoint1 : part number: 711-4030 711-4030B BulletPoint2 : Compatible with Waterway 711-4030 2" Gasket with Oring Rib BulletPoint3 : If your plumbing is 2" and your heater is 2" this part is correct. This version is the most popular version. 1 1/2 x 1 1/2 is 2nd most popular and 1 1/2" X 2 is 3rd most popular.This part is used in hot tubs to plumb a heater tube to a heater unio BulletPoint4 : Compatible Brand: For Arctic Spas, For Artesian Spas, For Beachcomber, For Bullfrog Spas, For Caldera Spas, For Cal Spas, For Canadian Spa Company, For Filbur, For Coleman, For Catalina Spas, For Jacuzzi, For Hot Spring Spas, For Marquis Spas, For Sweetwater Spas, For ThermoSpas, For Unicel, For Viking Spas, For Vita Spa, For Waterway Color : translucent ExternallyAssignedProductIdentifier1 : 0723497662826 ExternallyAssignedProductIdentifier2 : 723497662826 ItemName : WFCYQ 711-4030 (5) 2" Spa Hot Tub Heater Union Ribbed Gasket for Balboa Gecko O-Ring 7114030B ItemPackageDimensions_Height : 14.8082 centimeters ItemPackageDimensions_Length : 2.5908 centimeters ItemPackageDimensions_Width : 12.5984 centimeters ItemShape : Round ItemTypeKeyword : swimming-pool-and-spa-replacement-parts ItemTypeName : 2" Spa Hot Tub Heater Union Gasket Manufacturer : WFCYQ ModelName : 711-4030 ModelNumber : 711-4030 PartNumber : 711-4030 PowerSourceType : NO ProductDescription : 2" Spa Hot Tub Heater Gasket SupplierDeclaredDgHzRegulation : not_applicable