Carrier Supra 422 refrigerated unit. Can be used as refrigeration or freezer. Truck was just inspected in September. Good through September 2017. Passed with no problems. Unit was checked over by Thermo King as well. All the fluids were changed. This is a Diesel truck and both the reefer and the truck have their own engines. The truck does not have to be running for the reefer to kick on. The box is 12ft. long, 7ft wide and 6.5 high inside dimensions. People always ask me how much fuel it burns. I think its very good. I ran this unit for a strait week sitting (no truck running) at our county fair this summer at 34 degrees in the box and it used three quarters of a tank of diesel. A full tank is 30 gallons. The temperature outside reached over 100 degrees most days. On cool days it runs very little to keep Temp. It ha a 5 degree differential so if i have it set at 34 it will kick on when it reaches 39 inside the box.