This customizable mirror clip lets you choose the mirror thickness and overhang. It is made for a #6 screw and creates a countersink if you wish to use a drywall screw. The MCnoCS file is made for a 6 mm thick mirror with an 8 mm overhang and has no countersink. The MCwCS file is made for a 6 mm thick mirror with an 8 mm overhang and has a countersink so that the surface is flush with the V shaped screw head in place. The code is based on Matt Stultz's Parametric Mirror Clip.The countersink is made for a #6 drywall screw. I have had success with 2 shells, 20% fill.