Approximately 25mm gunmetal kidney ear wire components. 21 gauge. Plated brass. After attaching drop, use round-nose pliers to crimp loop closed. This keeps your drop in place. You can also string beads directly onto the wire (a French wire keeper, Bead Bumper or small crimp will hold beads in place when wire is opened/closed).
I have been very happy with these. they are not flimsy, nor do they bend out of shape. I found that sliding a bead on the wire, and then a bead bumper is a great way to keep the earring dangle from failing off.