Dimensions


1 Inch = 25.4 MM

These may help.

A penny is 0.750 inches in diameter or 19.05 mm

A nickel is 0.835 inches in diameter or 21.21 mm

1/8 of an inch = 3.175 mm

1/4 of an inch = 6.35 mm

1/2 of an inch = 12.7 mm

1 inch = 25.4 mm