Shower – How to remove this shower handle

bathroomfaucetscrewsshower

I am having a hard time trying to remove this shower handle. I am not sure what model it is (although it looks similar to some Kohler designs I saw on their website).

There is a hole under the handle but none of my allen keys or screwdrivers seem to be working in unscrewing this set screw. I tried wd40 as well, but to no avail. I am starting to wonder whether there is one at all, but if there wasn't why would there be a hole?

I tried removing the large screws holding the square to the wall, in case it was just one big piece, but the square seems to be a separate part from the handle itself.

FYI

  • I would like to remove it in order to adjust the rotational limit stop: the water coming out is either cold or scalding hot.

Shower handle

EDIT Adding a pic, not the best shot, sorry but I don't have a torch and had to rely on flash.

EDIT Managed to get it off and fix the issue. What did it was a torx key T10. Had to buy a set, but was worth it. Thanks so much for your help!

hole2

Best Answer

Definitely a "hex/Allen/socket" head set screw, you can plainly see the hex in your picture if you look close. I think you may have been using too small a key:

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