Yes it will keep them from sliding to the bottom. The hinge of the clip grips the string. When used for tomatoes the hinge is gripping a vertical string and holding up a cluster of tomatoes.

You still have to figure out a way to attach the clothes to the clip, however. It is a circle about 3/4" in diameter. Light socks can be poked through the circle. The sleeves of a light garment could be also be poked into the clip. Perhaps Toggles, buttons, clips or drawstrings could be attached to the clips. Depends on what you've got to work with.

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