This is my Drop-in replacement diffuser for Waterway Cluster Storm threaded jets using the 218-6550 style threaded diffuser, commonly found in many Strong Spas and other hot tubs. This version preserves the original function while using a simpler, more robust geometry that I have optimized for 3d printing. 

I have removed overhangs and made sweeps instead of hard angles. 

I would suggest PETG or ASA but have had success with PLA over the past few months. I will post an ASA and a PLA/PETG print profile as well as one with a .6 nozzle. I print at 100% infill as there is not a lot of extra material needed but adds strength. 

To install, Remove the existing Jet - in my case they were already missing. 

Clip the new diffuser on to the jet face, I have 3" and 2" jets that this works for. 

Test fit one jet before printing a whole set. 

For reference I have a Strong Spas Vienna.