Installed the unit under my backseat just on the other side of the wall from my engine and the dual 12v batteries in my 20ft Fish/Ski boat. Very easy to install, I did have to remove a small section of carpet so the screws (not included)would go into the wood, as per the installation instructions. Once everything was connected I plugged in the unit and it goes through a self-test, after about 2 minutes if all cables are connected correctly the unit starts charging the batteries. It took my 2 batteries a few hours to charge and then it went to a "condition" mode for a couple of hours then finally a "maintain" mode. I'll keep it plugged in until I use the boat knowing both batteries will be fully charged. The unit does get VERY HOT while in the "charge" mode, I guess this is why they want you to remove carpet and the like before you install. The cables and batteries do NOT get hot and the paperwork also says the unit will get hot, so nothing to worry about. I keep the engine compart open and the seat top open just for air circulation. I live in the desert and the garage does get hot in summer, but the unit seemed fine. The LED lights are easy to read and you'll always know what the charger is doing. Nice unit so far, haven't had to call for tech support so I couldn't rate that. Shipping was just 1 day, so very fast. The ProSport 44012 model is the Gen4 version and it costs almost $50 more, so I opted for this Gen 3 model. They both look identical, so up to you.