Shoreline Spas SL635L-18 SL635L Hot Tub Sterling Silver Int/Gray Ext: Step outside your fast-paced life and into the soothing, effervescent waters of your new Shoreline Spa. Now offering seven models, Shoreline Spas has the perfect fit for every spa enthusiast. Built to last and designed for comfort, Shoreline Spas offer everything discerning spa owners crave. Ample room and first-class amenities make for a winning combination while high performance pumps and a wide range of jets ensure a professional quality rubdown.