These are Y axis limit switch brackets for the Gatton CNC
The limit switches i used are
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https://www.amazon.com/gp/product/B00H8TJOU8/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
I used M2.5 screws to attach them,
https://www.amazon.com/gp/product/B012TE25QQ/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
The adjustable screw is a 10-24. The bumper for the head of the screw is hot glued on and sanded flat.