ProLine® Ultra-High Recovery units offer high performance for applications requiring highest hot water outputs. 6-year limited Tank warranty, 6-year parts warranty for Residential applications Aluminized Steel Multiport Burner - For even flame distribution, quiet operation and high-efficiency combustion. Combination Thermostat/ECO - With factory-preset pressure regulator and built-in millivolt-powered energy cut-off for overheat protection. Diffuser Dip Tube - Carries cold inlet water deep into the tank to minimize temperature dilution of hot water, and helps reduce scale buildup to extend tank life. Fused Ceramic Shield - A tough, thick, durable coat of blue ceramic is fused to the tank’s interior surfaces at 1600°F, forming a corrosion-resistant lining for years of dependable protection and use. Non-CFC Foam Insulation - The tank is surrounded by a thick coat of non-CFC polyurethane foam to trap heat inside the tank, saving energy. Side T&P Valve 1/2” Gas Connection Anode Rod - Top-mounted, heavy-duty anode for added tank protection, extending the life of the tank. Code Approvals - CSA International certified, CEC and NAECA requirements. All models are certified at 300 PSI test pressure and 150 PSI working pressure. Drain Valve - Durable, brass drain valve. Low NOx - Meets NOx emissions of less than 40 ng/j.