Model GC10A-4E. Ten gallon capacity. 10,000 BTU. 15-1/2"W X 16"H X 20.8" Overall. Atwood water heaters are designed so that more than 90% of the heat produced by the pilot light is utilized to maintain water temperature eliminating much energy waste. Atwood's heat transfer system with patented U-tube design delivers more hot water. Access to all the controls is as easy as opening the access door. All gas lines are connected in a sealed combustion area which is vented to the outside of the vehicle as a safety precaution. For use in RV's only.