88mm, 89mm, 90mm Onga Classic Jet. Used in spas and pools in the 1990s. These were discontinued in the early 2000s and there is no replacement. The entire body and jet will need to be replaced.
The hole diameter in the spa may require enlarging to accomodate replacement jets.
The best replacement option depends on exact hole diameter in the spa shell, the type of plumbing to the original body and whether the plumbing is above or below ground level.
Contact us with images of the plumbing and hole size info for replacement advice.