1-inch Air Control plunger/diaphragm part 662-2140 is used in select 1 inch Waterway air controls.
This part is just the plunger.
We also offer a 1 inch air control upper seal
Hydro Air 1" Air Stem Cap Assembly White 50-2108WHT Top Draw Air ControlPart only WG/HAI Slimline, 1" White, Top Draw Replaces 611633 , 76246 , 9369-02 , HA502108 , HAI-85-7427