Force Fit Grommet, available in Nickel. Small measures .39″ (1 cm) inside diameter, Large measures .59″ (1.5cm) inside diameter. Premium quality. Sold per piece.

To set grommets: Create a hole in the fabric the size of the grommet opening. Place the half with the larger opening on the back side of the fabric. On the right side of the fabric, insert the piece with the smaller opening. Set in place by forcing the two halves together with a rubber mallet.