About this 3D model

I made to so I can put 12mm x 3mm magnets on the Black Widow to hold tools 1 - 10mm thick will hold 3 magnets uses 16mm screws and T nuts2 - 10mm thick will hold 6 magnets uses 16mm screws and T nuts3 - 5mm thick will hold 3 magnets uses 12mm screws and T nuts