Guess the M3 screw?

[Newmarket]

The ones on the left you'll find in computers and DB style sonnectors, those are not metric M3.

Not 100% though. Some connector manufacturers do use M3 on SubD etc.
I know as have been there with bits that just wouldn't fit together properly.

 

[Ilya]

Some connector manufacturers do use M3 on SubD etc.

DB connectors indeed can have both metric and imperial screws. You never know which you've got until you have the gear at hand. Good luck trying to find this out from the manufacturer. This is especially frustrating when you live in EU or other metric region that basically has zero imperial DB stuff in stock anywhere.

 

[Newmarket]

DB connectors indeed can have both metric and imperial screws. You never know which you've got until you have the gear at hand. Good luck trying to find this out from the manufacturer. This is especially frustrating when you live in EU or other metric region that basically has zero imperial DB stuff in stock anywhere.

Yeah - my experience comes from changing backshells to help EMC compliance. Let's just settle on metric as a global standard