MPCNC tool mount Duro DCT 160 / pen holder

I needed a tool holder for my dremel clone - Duro DCT-160 (Aldi), which should be a clone of the dremel 300, but I can't confirm that.

I made use of the design by tkbletsc openscad project and added a second hole for the clamp and the back for the MPCNC tool mount (F version, 25mm center-center distance).

lower part diameter 18mm
upper part diameter 55mm

Unfortunately the tool is not exactly round. The maximum diameter is 55mm at the black grip.
The tool mount has not been tested so