Here is an awesome 4 Piece Combo Kit, for the most common and popular Spa and Hot Tub 2" Split Nut Heater Union, used all 2" Heater Assemblies made by Balboa, Gecko, Hydro-Quip, Spa Builders, Correct-Tech, Applied Computer Controls and many others. You get 2) 2" Spa Heater Split Nut Unions and 2) 2" Waterway Gasket/O-rings, all for one low super low price. When ordering, important to know, that threads measure approximately 3" on any 2" Split Nut. Purchase more than one of this combo and receive an extra 5% discount.
****** Important Note ****** Actual Thread Measurements on ANY 2" Split Nut is approximately 3"