Clip-in hair beads come in packs of 10 and measure about 12mm in diameter when they're completely closed. They are made of plastic and snap into place. There are little teeth (spikes) on the inside of the beads to hold them in place, so they can be used on chunks of loose hair as well as braids, twists, and dreads.
Size: 12mm x 7mm with a 10mm opening.
Brand: I Kick Shins.