Hot Tub Replacement Part compatible With Watkins Spas Air Check Valve, fits Hot Spring Models 70289. Air check valve fits Hot Spring all 1993-2001 Models, fits Tiger River all 1997-2000 and fits Hot Spot spa all 1997-2002 models. This check valve is located in the equipment compartment under the bartop. Its primary function is to prevent water from back flowing into the equipment compartment should a hydrotherapy jet become obstructed (like when a guest sticks their finger in the jet). Sometimes this check valve can make a loud vibrating noise as the silicone diaphragm ages behaving like a reed on a flute.

• This is for a Single Air Check Valve 
• Compatible with Watkins fits Hot Spring Models
• Note: These check valves age at the same rate. It is best to replace all of them at the same time if budget allows
• Length: 3 1/2 Inches
• Diameter of opening at the top: 1/4 Inches