Hot Spring Motomassage Jet (For Duel Moto Jet Systems) Part Number: 73542 Moto Massage replacement for DX Motojet System. The Moto-Massage is a jet that automatically travels up and down to massage a person's back. The mixing of air and water in a jet along with a plyable spine causes the sweeping motion of the Moto-Massage. Fitment for 2005- Current Hot Spring Spas. Hot Spring Spa Supplies carries spa fragrances, air & water valves, control systems, filter accessories, lights, cleaners, pumps, thermostats, and more for virtually every hot spring model.