Regency pleat hooks for making small pleats in lightweight curtains. These curtain hooks can also be used as a standard tape hook. Suitable for curtains with heading tape.
Other companies make their own versions which are slightly smaller and often found on boats, planes tracks, caravans etc.
Regency went out of business around 2016.
I may still have a few of these left, get in touch
NOTE sold in quantities of 1, photo for illustration.