BCW 100 Premium 2 X 2 Penny Size Coin Holders 100 New BCW Premium Brand Cardboard Fold & Staple Coin Holders. Made of Cardboard and Crystal Clear Polypropylene film. Coin Safe! Polypropylene will not react with any metal. No PVC-No Acid-Coin Safe Cent/Penny Size - 19 mm. 2X2 inch BCW Brand Cardboard Coin Holders