The MPPT WireBox fits over the base of Victron MPPT Solar Charger and provides an extra level of safety. It’s particularly useful if your MPPT Solar Charger is installed in a general access area. It covers all DC terminals, preventing accidental or inquisitive contact with terminal screws. This wirebox can be used with MC4 style controllers for the following sizes: 150-45, 150-60, 150-70, 250-60 and 250-70 controllers.