Sundance, Jacuzzi, Thera-Max, Thera-Flo, 2" Flat O-Ring Replacement that is Round..

This O-Ring is a replacement for the Square Gasket that is found in the Sundance, Jacuzzi, Thera-Max, Thera-Flo, 2" Flat Style O-Ring.. 
Heater Union Part Type    O-Ring
Part Type    O-Ring
O Reference Number    O-151
Inside Diameter    2-9/16"id
Cross Section    3/32"
Kit    No
Application - Category    Filter, Cartridge, Filter, DE, Pump, Spa
Application Manufacturer    Generic, Jacuzzi/Carvin, Generic, Purex/Pentair, Generic, Sundance, Generic, Vico/Balboa, Generic, Waterway
Application Model    Bracketless 48 Frame 60HZ J-200, Bracketless 48 Frame 60HZ J-300, Bracketless 56 Frame 60Hz J-300, Bracketless 56 Frame 60Hz J-400, Bracketless 56 Frame 60Hz J-LX, Bracketless 56 Frame 60Hz J-XL, Crystal Water, Fixed Bracket 48 Frame 60Hz J-200, Fixed Bracket 48 Frame 60Hz J-300, Purex CFM, TheraMax/TheraFlo, Ultima
Application - Part    Manifold, Standpipe, Union
Manufacturer Part Number    6000-645, 74021, 805-0145, O-151, U9-203
AS568 Number    145