The coin flips fit perfectly in our Acid Free sheet which assures your coin 100 % safety from moisture. Both sides of the coin are visible. These packet includes 10 different sizes of cardboard coin flips which are 17.5 mm, 20 mm, 22.5 mm, 25 mm, 27.5 mm, 29 mm, 31.5 mm, 33 mm, 37 mm, 40 mm Colour: white cardboard flips Capacity: 10 boxes inside, with each 25 coin flips total 10 different size