This is a holder to attach a microSD extension cable to 2020 aluminium extrusion. I designed this to attach to the front of my FLSUN Kossel to give me easy access, via the extension cable, to the microSD socket on my RADDS board. The board is housed in the base of my delta and therefore difficult to access.

The holder is designed to form a pressure fit with this type of extender:
https://www.aliexpress.com/item/2016-Hot-sale-48CM-TF-to-micro-SD-card-Flex-Extension-cable-Extender-Adapter-reader-car

Secure the holder to the 2020 frame with an M4 hex bolt and appropriate T or square nut. Then feed the ribbon cable through the slot in the base of the holder and push the extender body into place. I'm sure this would also work fine with 1515 extrusion and other types of printers.