SunStar Heating Products Garage Tube Heater - NG, 25,000 BTU, Model# SIR25-15-N Compact size: overall length is 110in for ease of installation Efficiencies range up to 84.5% Installation as low as 8ft. above floor CSA design certified Vacuum System pulls combustion products through the combustion chamber for greater safety, virtually eliminating the possibility of combustion gases leaking into the heated space