6600-166 Sundance Spa Short Housing Temperature Sensor With Curled Finger Connectors. (Old Part Numbers: 6600-070, 6600-184, 6600-637, And 2000-637). Fits All Portofino/Sweetwater Systems. Also Fits 1998+ Solo, 701, And 724 Systems, 2003 - 2005 Del Sol Systems, 2006+ 780/680 Series, 2011+ Elite Series.
O-ring Sold Separately, Part Number: 6540-228