These screws have always annoyed me. Particularly on aftermarket caps the Phillips is too soft and you can't actually get on the outer hex because the wall thickness of basically ANY socket is too great.

What do you guys do? Dumbest design ever.

 

Soft? They are hard to get to but don't have any other issues with them. I believe they are #1 Philips but different manufactures may use different heads. I use a mirror to guide the screwdriver to the screw.

 

Doesn't something like a 1/4 inch socket work on them as well? Maybe 5/16ths?

 

7mm but as I said the w.t. of any socket is too great. That's aftermarket. OEM may very well have put a fractional head on a metric thread.

I swapped in M5x0.8 SHCS and now it's 4mm hex. Much better