I purchased this at a department store event a few years ago. It's 3.0mm thick and can be put in the pocket of your wallet to add an accent and increase the number of cards you can carry. The color should be black silver. Please be aware that the actual color may differ from the photos. Color: Black Silver Material: Genuine Leather "3.0mm Thick Card Case" Ultra-lightweight and simple card case. Can hold up to 10 cards (front and back). There's also a side pocket, which is convenient for storing receipts. It's the same size as a 10,000 yen bill, so you can also put the card case itself inside a standard long wallet. Keep your wallet contents neat and beautiful. ≣ Material / cow leather (shrink leather) ≣ Size / 7cm (H) x 15.7cm (W) ≣ Color / 17 colors ≣ Price / ¥6,820 (tax included) VIFJ / Vifjei Card Case Long Wallet Wallet Thin Wallet Women's Ladies