THESE SWITCH COVERS ARE MADE OF HARD PLASTIC AND WHEN PURCHASED THEY HAD SOME ISSUES FITTING THE ST16, SO WE PUT THEM IN A MILLING MACHINE AND RELIEVED A SMALL PORTION OF THE UNDERSIDE OF THE PLASTIC COVER SO IT WOULD SET COMPLETELY SET DOWN OVER THE SWITCH, THE BEST WAY TO ATTACH THESE ARE WITH THE APPLICATION OF A SMALL AMOUNT  OF ADHESIVE UNDER THE METAL BASE PLATE.

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