This clip replaces the original clips that come on the clothes horse that become brittle in the sun.
Print it at 100% infill with the open end down, I found that I could print a bunch at the same time without too many issues.
Since it is a mechanical part I would use a harder flexible filament, I used 3DFillies Flex PLA because it prints with a regular PLA profile but it is only available in Australia so you may have to find your own material.
The author hasn't provided the model origin yet.