Convection Poly Tube Heating is arguably the most cost effective & efficient method of heating poultry sheds today. How do convection tubes work? Poly tubes release hot air via pre punched air holes, evenly spaced the full length of sheds & suspended overhead by cable supported straps. What is the heat source? Biomass hot air blowers provide the most efficient, cost effective dry air heating available - important for a healthy poultry shed environment. D'Alessandro GS/GSA130-