The Mazzei White #884K Ozone Injector is used on hot tubs with a 2-speed pump or large circulation pump.
3/4 Inch - Hose Barb Connections.
If your circulation pump is larger than a Waterway Tiny Might Pump, this is the correct injector to use. It works great on large 2-speed pumps and circulation pumps like the Waterway Iron Might and AquaFlo Circmaster. If you have a tiny circulation pump, then use the #684K Red Injector.
Mazzei Brand Injectors are Highly Recommended.