50mm, 75mm and 100mm sanding disk holders. They are 45mm deep each, but I've uploaded both Fusion and STEP files, so they are easily adapted to the size you want. In my case, I combined the 50mm holders to give me a row of three and combined two 75mm holders, which would be the maximum width capability of my 220mm print plate.

Update. I have now uploaded the correctly sized 50mm holder