Some calendars come with a date window, some come without it. This allows adding one to your calendar with three printed elements, piece of string and a rubber band.

Print instructions

Prints well using PLA and 0.2mm layer height.

Print 1 date window and two rubber band holders

Assembly

Use a single piece of string to connect all the pieces together and a rubber band to tension the string at the back of the calendar (see photos). The date window should slide on the string and the tension shouldn't be too strong (or the calendar will not stay flat)