The Giant® 50 gallons US, FVIR high-performance natural gas residential water heater, is equipped with a high efficiency 40,000 BTU burner, silicon nitride igniter and a factory installed safety valve. It also features a brass drain valve and 3/4 NPT dielectric connections. This model is certified from 0 to 5000/ altitude and can be evacuated with a 3'/ to 140' PVC vent. It offers better thermal efficiency and better energy factor. It has a stainless steel baffle for better resistance to heat and a manual reclosing high temperature switch to enhance safety. Its high-quality magnesium anode offers excellent protection against the corrosive effects of water. In addition, its GreenFoam® ecological foam insulation contains no HCFCs, CFCs nor VOCs.This product is manufactured in Canada and is covered by a 6-year limited warranty against perforation of the tank and parts from the date of installation.