I recently got a Smart Battery Protect 12/24 | 65. It came with a wire to connect to ground - but I have no idea what the gauge is.
Here's the manual: https://www.victronenergy.com/upload/documents/Manual-Smart-Battery-Protect-12V-24V-65-A-100-A--220-A-EN-NL-FR-SV-DE-PT-ES-IT-TR.pdf
Here's the datasheet: https://www.victronenergy.com/upload/documents/Datasheet-Smart-Battery-Protect-65-A--100-A--220-A-EN-.pdf
No info in there unfortunately - anyone know what gauge/mm3 wire it is?