The Waterway Massage Jets are professionally designed jets that combine sturdy engineering with a sleek, high-quality model. Designed with extra large 7 1/2 construction, they are available with adjustable flow control and offer easy through-wall installation for hassle free set up. These Massage Jets have a 3/4 nozzle and a 75 GMP flow for comprehensive water flow. Its two ball bearings ensure added longevity for an enhanced lifespan. Massage Jets are installed into 1 1/2 x 1 1/2 plumbing and are available in both plastic and stainless steel options.