1.Replace for , for heating coupling replacement parts, 2.Hot tub pump and heater, replacement parts for hot tub heater, hot tub heater and pump kit Replacing hot tub heaters,for hot tub components, for pump replacement parts, replacement parts, swimming pool and spa replacement parts, for hot tub replacement parts, and for spa replacement parts [Applicable]for Jet spa centers, including for , for , for Hawaii, for Helsinki, for spa centers, etc. This grey coupling connThis grey coupling connector can be found in the ends of the B & C (Water Flow and Return) pipes compatible with or Air Jet pump. Compatible Model:Fits Springs, for Honolulu, forMilan, for . , for Paris, for Cancun, for , for , for AirJet, for , for Colour:grey Material:plastic Package Contents: 1 x Expansion nut Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.