Here is a 3/4" Barb Fitting Repair Kit, Pair with O-Rings for a Watkins Double Barrel Heater. A Life Saver. Whether you need the Gaskets or Barb Fittings or both, this is a fabulous parts kit that will save you big bucks, not having to replace an entire heater. Spa Techs and DIY's love this kit and End Cap Turnaround Kits too.