Response Technologies, Inc.: Operating from vehicle`s battery system, System 70 uses thermoelectric heat pump to heat and cool an insulated compartment automatically. It operates electronically, thus eliminating the need for fluids, gases, and compressors. A digital controller, a temperature probe, and a custom electronic interface are included. An optional backup battery maintains heating and cooling while vehicle is running, parked on shore power for up to five hours or more without disabling