Thermaxx Refrigerated Truck Bodies have the lowest ‘K’ Value in Australia. ‘K’ Value is a value of the amount of thermal conductivity of heat, in watts, that is transferred into a truck or trailer body through leakage or failure of construction materials. In short, if your panel is inadequately insulated or the construction methods are substandard you will have a HIGHER ‘K’ Value. The LOWER the ‘K’ Value of the completed body the HIGHER Thermal efficiencies you will have.