The Powerblanket tank warmer GCW420 is an electric insulated electric heating blanket for 420 pounds of Propane or other compressed gas. This gas cylinder warming blanket uses 120 Volt power and provides 960 Watts (8.00 Amp) of heating capacity. At 53 inches in height, this Powerblanket tank heater is engineered to maintain the temperature of a 420-lb. liquid propane (or other gas) cylinder tank at optimal temperatures by helping maintain pressure, enhance performance and increase efficiency. UL/CSA/ETL Certified - U.S.A. (* Results are contingent upon boundary conditions)