The Oscillater JetPak is one of the most popular massages in the JetPak Therapy System. The 4 large propretary Oscillator jets give you a unique figure-8 kneading massage that is smooth and relaxing. This is sure to become one of the favorite JetPaks in your hot tub. Learn more: www.bullfrogspas.com/listings/custom/122/45/oscillator The JetPak Therapy System by Bullfrog Spas is the only modular hot tub jetting system that can be personalized specifically for you. You choose your jetting configuration, intensity, and the spa seat in which you prefer to place each JetPak. See more at: www.bullfrogspas.com/jetpaks