Balboa M7 5.5 kW [15" x 2"] FloThru Spa Heater (G7512) adhesives This version is especially useful This version is especially useful for supported post 5 03 systems requiring the B4 style application 0kW heater pairing is a key part of this system’s value because it keeps the electrical and thermal side of the setup aligned That can make the final repair feel much more like restoring the spa than changing it into something else 5 kW Spa Heater Assembly is designed for compatible 2 inch by 15 inch applications where the original heater has become inconsistent or has reached the point where replacement makes more sense than continued troubleshooting