Clear case 40mm quartz drum made of durable, scratch resistant acrylic. Lockable and easy to open. The thickness is compatible with regular coins, and it is not suitable for heavy objects such as piefors and ancient coins. Also, if you force it into a small inner diameter of 0.04 inch (1 mm) may cause damage. Please check the diameter and thickness of the coin before ordering. The total size is just the right size, so if you purchase a 0.0004 inch (0.01 mm) larger coins, you will not fit. In addition, even if there is too much room for the coins to move within the capsule, please be sure to check in advance.