Approximately 30mm kidney ear wires. These earring hooks are 22 gauge. Plated brass. White plate is the "silver" color most often seen on base metal jewelry and components. Kidney ear wires hook completely shut which allows you to make extra-secure earrings. White plating is also known as "imitation rhodium" and "silvertone". 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).