Our combiner box (C-Box) is custom made by AM Solar for efficiently combining solar panel output cables and sealing off a roof penetration. It’s rugged and spacious design make installation and troubleshooting very easy. It is the most efficient way to install a lot of solar with only a single penetrating hole through the roof. It has eight possible ports and can use up to 2-gauge cable, which allows for installation of larger solar arrays. We have installed as many as 16 solar panels (1600W) onto one roof using just one C-box (in 8 series pairs). It has a very small footprint for its available capacity, and it is sealed to ensure that it is completely waterproof.