Rubik's Cube Center Cap

This is a model of a standard shape and size Rubik's cube center cap. Another file includes the center cap with an extension that fits the shaft of the BYJ48 stepper motors such as these: https://www.amazon.com/gp/product/B01CP18J4A/ref=oh_aui_search_detailpage?ie=UTF8&psc=1.

Center_cap is just a standard sized and shaped center cap.
Center_cap_with_hole is a center cap with a hole removed for my specific drive shaft.
Center_cap_with_shaft_and_hole is the same as the above file but include