Sold as pair. These plugs are made up of 316L Surgical Steel. These plugs have a spider web design. The plugs are screwed fit in the back. The sizes available are 2 gauge, 0 gauge, 00 gauge, 1/2 inch, 9/16 inch, 5/8 inch, 3/4 inch, 7/8 inch and 1 inch. These items are completely nickel free.