The Mainstream Whirlpool Drop-In Tub from American Standard treats you to a spa-like experience at home. Soothe sore muscles, relax, and indulge in the therapeutic benefits of eight strategically placed, adjustable jets designed for allover or targeted relief. Our exclusive EverClean silver-ion additive is molded into the circulation piping and jets to inhibit the growth of bacteria, mold & mildew.