This part is a Waterway 1" Spa Hot Tub Air Control Valve with the hidden type cap to be used under a larger handle style cap. You use this valve to replace the guts of an installed valve and don't use the body.. The Valve Cap Width is approx. 2 11/16"...
This valve can be found on many hot tubs with a large cap knob like Cal Spa and Catalina as well as others..
