Aimpoint PRO Rotary Switch Issue

Just picked up a new PRO. The rotary switch (led intensity dial) fell off first time at the range. Looks like it was held in place with two roll pins or maybe set screws, I can’t tell. If set screws, I can’t tell what kind of driver it takes. Anyone know how these are held on?

Here’s a couple of lousy iphone pics, if that helps.

Edited to say that it still works fine, other than the rotary switch doesn’t stay in place on its own.

It’s a small hex.
I can’t remember exactly what size, will take some trial and error.
Once you find the size that fits, be sure to use some thread-locker to keep it in place.

Thanks, I’ll give it a go.

Edit: 1/16 in. worked like a charm!

Lucky you found it.