Victron MK3-USB Configuration Interface
The MK3-USB C allows the following products to connect to a computer for configuration and firmware updates using the Victron VE Configure software
Multi, MultiGrid, MultiPlus, MultiPlus-II, Quattro, Inverter/Charger settings in ECOmulti, EasySolar, EasyPlus, and other Inverters with a VE.Bus communication port.
Counsider purchasing a Cat 5 ethernet cable to go with this product if you don't already have one. You won't be able to connect the MK3 interface to an inverter product without an ethernet cable.
The VEConfigure tools are only available for Windows. For Mac, there is a (not officially supported) work around available.
Victron Connect is a cross-platform tool and for most programming options, you can use this app.