For indoor or outdoor installations on commercial pools and spas. Features include an LED temperature readout with dual thermostat controls, temperature safety lockout, and 6-position control panel. PMG burner technology requires no outdoor draft hood. Proven Dura-Glas rust-proof construction with plastic manifold and brass connections. Heavy-duty unit with optional cupro-nickel exchanger stands up to the harshest of applications, like low pH, high flow or heavy use. ASME rated for commercial applications.