This 4 Function, spa-side remote is completely weather resistant and is designed to be installed above water level in the spa tile line, decking or anywhere outdoors in conjunction with any model AquaLink RS. Spa side control of desired water temperatures and other pool/spa features. Install up to three (3) Spa Side Remotes on one (1) AquaLink RS system. 2-3/4-Inch in diameter. 1-Inch to 1-1/2-Inch, 100-Feet size.