High quality 4mm open end wrench?

[Renochs]

I have a few hundred cable rails to attach on a deck and they require a 4mm open end wrench. Unfortunately the only ones I can find are cheaply cast "toy" wrenches which are sloppy and will not hold up for the job. Does anyone have suggestions on where I can get a couple of well made wrenches this size? If I could find one about 3" long that would be even better.

 

[FB-eye]

This size will be hard to find in good quality. Have you looked at precision or jeweler's wrench sets? they come in smaller metric sizes sometimes with better build quality than the standard hardware store stuff.
Alternatively, some people have luck with automotive feeler gauge wrenches or ignition wrenches in that range

 

[Renochs]

I found this one on amazon. It's made for adjusting turnbuckles on remote control cars. But it looks like it's pretty well made so I'm going to try it out and will let you know what I find. https://a.co/d/aqz8EqO