You are buying a 1 1/2" Heater Split Nut Only which includes the split nut and (2) Screws for use with a 1 1/2" Heater Union that would measure about 2 3/8" OD... The Heater Flange Split Nut mounts to the heater tube using 2 screws to hold it in place and screws onto the heater threaded union with a gasket between the union and tube. Please see our store for a kit that includes the gasket. If your plumbing is 1 1/2" and your heater is 1 1/2" this part is correct. This version is the second most popular version. 2 x 2 is 1st 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 union. Note: The Heater tube in pictures is NOT included!! NOTE: The colors of the split nuts may vary.
