This is a generic head mount for a Doxy Die-Cast 3. The 3 and 3R both have removable heads meant for various attachments. This model fits the 3 and 3R. It's not meant as a replacement head on its own, but rather is a stepping-off point for future models, remixes, et al. 

The head is 45mm in total diameter, 21mm high. Inner threading diameter is 34.5mm, 8.25mm high. The inside threading is 1.0mm pitch. There's an open chamber above the threads to accommodate the rest of the device. It was produced with OpenSCAD using the BOSL2 library.   

This model was successfully printed with a Prusa i3 MK3S+ using a generic PLA filament, with PrusaSlicer's built-in 0.10mm DETAIL settings, in basic mode. Print time was approximately 2h38m.