mirobenI designed this calendar hanger with an integrated pen holder so we could hang our calendar from a Command hook and never need to search for a pen to write on the calendar.
https://makerworld.com/en/models/1929326-calendar-hanger-with-pen-holder
Calendar Hanger with Pen Holder by miroben MakerWorld: Download Free 3D Models
Calendar Hanger with Built-in Pen HolderA convenient way to store your pens with your calendarThe location for our calendar has a large Command hook that is too big for the calendar to hang from. We were frequently looking for a pen to write on the calendar. This was my solution that has been working great for us so far. The calendar peg has a diameter of 3.5mm. This is designed around the large hook we have, but should work with a nail or screw that sticks out from the wall at least 17mm. The attached profile is using "0.12mm Fine" in order to smooth the curves around the top. If you want to save time, you should be able to print at 0.16mm or 0.20mm. If you print this, please consider sharing pictures of your print.