Wide Application? This heater is specifically designed for Value Series and M7 Series Spa, which is a perfect replacement for Balboa part # 58083. Important Specification? Heater Length: 15″, Heater Diameter: 2″. 5.5KW, 220V heater element. Please choose correct rated heater for replacement and put it in right position to extend the service life of the device. What You Get? Package includes 1 heater, 1 pair of 2. 0 heater split nuts, 1 pair of 2. 0 heater tailpieces with o-ring gaskets. Superior Construction? The heater housing is made of premium stainless steel to prevent corrosion and rust, sturdy and wear resistant for providing excellent performance and lasting service time. 5 Tailpiece, 58209, 58000, 58010 (825 Incoloy), 58123, 58089 (Incoloy), 58086, 58105, 58016, 55473, 58140, 58306 (Has BP Heater Cable), 55624 (Has Titanium Element), Master Spas X300713, 58016 (Marquis Spas). We will respond within.