I just had mine installed this weekend. Yes I agree the size of the unit that's mounted inside the car is the size of soda can or a bottle of water. Mind RV is a 2007 National Tropic-Cal LX T370 on a Freightliner chassic that was already pre-wired for this unit. I'm very pleased with the unit and it works great. I founded out directly from US Gear that the best place to buy this unit was from PPL Motorhomes in Houston, Texas. I paid ~$800 for model #UTB-1000 which is the model that includes everything needed for the car as well as for a non per-wired RV. Good Luck.