All spas are equipped with Sta- Rite Max-E-Therm heaters. Features include LED temperature readout with dual thermostat controls, temperature safety lockout, and 6-position control panel. PMG burner technology requires no outdoor draft hood. Utilizing the proven Dura-Glas® rust-proof construction and PVC union connections, longevity is the outcome. Heavy-duty unit with cupro-nickel exchanger stands up to the harshest of applications, like low pH, high flow or heavy use.