The Temperature Sensor usually mounts into the wall of the Spa. The boxed end plugs into mounts onto the PCB.
Diameter: 20mm
Cable length: 3.5mm
Commonly used with: Sundance Hot tubs. The Boxed End version is mainly used for the luxury 850/880 systems including Maxxus, Cameo, Optima, Alimar, Marin and Capri.