The ZX Microdrive is a magnetic tape data storage system launched in July 1983 by Sinclair Research for its ZX Spectrum home computer. The Microdrive technology was later also used in the Sinclair QL and ICL One Per Desk personal computers
This is the spare part for the Microdrive tape Cover
Please pay lots of attentions in removing the internal support (if you have it) in order to do not damage the microdrive tape.
Other Sinclair parts: https://www.thingiverse.com/Matto68/collections/sinclair-ql