5.5 KW replacement M7 heater with stud for use with many Balboa VS and SUV based systems that utilize two heater sensors. The heater tube has an inside diameter of 2" and a flange to flange length measurement of 15". The union connections for your plumbing are considered 2" but measure closer to 3" across the inside female union thread. This heater includes the two split nut unions, tailpieces, gaskets and two sensors. The torque value for the electrical connections on this heater are 30-35 Lbs

Since this heater has been used industry wide on one of the most popular platforms out there, its hard to name all the manufacturers or controls that have used this heater, so here are the most common: Gulf Coast Spas DX and EX5000 models, Centurion Spas, Garden Leisure Spas, Shoreline Spas, Great Lakes Spas, Dynasty Spas, Cool Nights Spas, St. Lucia Spas, 864Lei, 854in, 864co, Platinum I, Platinum II, Legend Spas, Hydro Spa, Premium Leisure, Leisure Bay, Artesian Spas, Island Spas, Marquis Spas, Spa Mfg, Alps Spas, L.A. Spas,  and many more. Mates to the Balboa VS control systems such as the VS500, VS501, VS510, VS511, SUV Digital, SUVM7, HS200M7.