Expanded Metal Corner Beads :

Corner beads can be supplied in expanded metal or perforated metal, mainly used for plastering of walls. Finishes can be hot dipped zinc coating or electro galvanizing.

Expanded Corner Bead has a smooth round nose bead with diamond mesh wings for the keying of plaster right up to the nose of the bead. On the outside is the finished edge which is where one side of your drywall knife runs on when you are applying drywall mud. The two flanges sit flat on your raw drywall. The diamond decoration along the length of the flange acts as a keyway for holding the drywall mud to the drywall and the corner.