The Firestorm Gen ii Tech Heater system features a highly efficient exchangerdesign to minimize heat dissipation compared to older generation heaters.The result is maximum heat consistency and higher BTU ratings. This heaterwill keep your sealed cab comfortably warm in the most extreme coldconditions. Designed and Engineered as an integrated solution, there are 4dash vents and switch that inserts into one of the pre-set switch knock outson the dash switch panel. The result is a factory level installation solutionand not a box bolted to the floor. Adjustable vents provide maximumdirectional options to get the heat where you need it. Top vents can be used for defrost as well as directional heat, and bottom vents can heat your legs and feet.