Please unbutton the button and insert your card. There is a pocket on the outside. How about an ID card holder that's uniquely yours, different from the rest? We make each item with care, but as these are handmade, please refrain from purchasing if you are looking for a perfect product like a mass-produced item or if you are overly concerned with details. ● Card Size Length: Approximately 5.5cm Width: Approximately 8.4cm ● Material: Cowhide ● Other Notes Please be careful of water damage.