As excerpted from a vintage fashion website, "There are many styles of vintage clips used. Some were pairs which clipped onto shoes to dress up a plain pair of pumps. Others were fancy clips used on fur stoles and light weight dresses. Combination brooches also has special mechanisms so that the pair could be worn as a single clip. "
I recently started collecting vintage dress clips and find them very interesting.
Dress clips have a piece of metal which has "teeth." The teeth are intended to grasp thin material such as a dress or shirt. Some dress clip backs were flat hinged pieces of metal, or wired mechanisms with no decoration at all. Others were made of ornately filigreed metal.
Merci and au revoir!