Like Doddy, I use XLR connectors for my steppers. Ideally these should be hard-wired but I found that I was taking the control box in and out of the router frame quite a bit while building and testing and the XLRs work fine in practice. I also use those "aviation" connectors for signal wires (limit switches, VFD control connections, etc) and they are fine for that. I bought a bag of 5 or 10 from eBay or Aliexpress or somewhere like that fairly cheaply. I think they were described as "GX16", and come with various numbers of pins. Watch for the ones with a lot of pins - they aren't the easiest thing in the world to solder if you aren't a dab hand with a soldering iron!