Hi,
It looks like a combined connector for
* standard 4 mm type connectors
* direct cable connection.
Choose any suitable cable (We don´t know the length, the current, the acceptable voltage drop....thus it´s impossible to give a recommendatin)
--> calculate the acceptable resistance using Ohm´s law. Then divide this value by the cable length. then find a suitable cable diameter using tables.
Choose wheter you want a 4mm connector or not. There are more than enough suitable connectors in about every electronics shop and catalogue.
Klaus