The MK3-USB allows the following products to connect to a computer for configuration and firmware updates:
Multi, MultiGrid, MultiPlus, MultiPlus-II, Quattro, Inverter/Charger settings in ECOmulti, EasySolar, EasyPlus, and Inverters with a VE.Bus communication port.
This unit allows you to upgrade the firmware and to program the above units
Victron Connect app is also needed, this is a free download app, or you can also use Victron config on your computer as well.