The invention consists in the combination of means in a clip to enable the clip to move freely on the rod of a clothes rack, to any position desired, but looking the clip to the rod, when the clip supports any article of wearing apparel or the like. The invention includes complementary rod holding recesses, one in each jaw member in the handle portion thereof, so that when the handles are pressed together, and the jaws opened the rod is lockingly embraced to hold the clip to the rod against longitudinal movement.

https://patents.google.com/patent/US2583784A/en?inventor=mario+maccaferri&oq=mario+maccaferri