Spartan PowerT Branch 3 to 1 Connector Parallel Solar Panel Cable Connectors MFFF + MMMF

How many panels can you add with these?

Can i use this as a 1 to 3 connect? I want to charge my jackery 500, my rockpal 500, and run my 12v frig from single solar cable coming in to house.

Is this a 3mm squared connector (mc3) or 4mm squared (mc4) ?