This Water Heater Bfg Tstat Propane with 1"" Insulation, Oem Replacement for Premierplus Bfg Models, Right Hand Universal Thermocouple Thread, Natural Gas and Propane Models Fits Up to 50 Gal Units, 2"" Insulation, Gallon Capacity: 30 40 50 Gal, SKU: HMREX875