Waterway Poly Storm 3 3/8" to 4' Face Jet Internals are all Interchangable so choose for the therapy that you would like. On these new jets the back may look slightly different as the design is the same but the plastic is slightlty thicker looking as they have improved the jet back to last longer. Available in Smooth Face and Scalloped Face. Most Jet Inserts are available in White, Grey or Black.