Waterway Poly Jets are characterized by their wide, barrel-like body. The older style poly jets may not have a trim ring. The face diameter varies from 2 5/8"-3 3/8". Poly jets turn clockwise to be put in place. They can have a cone shaped end, or flat. Flat is much more common than the cone style.
Waterway Poly jets are quickly becoming obsolete. They are not typically used in spas much past the year 2000. Get them while you can!