Diamond Supply Stone Wallet two tone velcro folding wallet with cash slot, three card slots and ID card slot. Fabric: Textile Leather. Available in one size. The modern bi-fold wallet with multiple "card slots" became standardized in the early 1950s with the introduction of the first credit cards. Some innovations include the introduction of the velcro- closure wallet in the 1970s. Pocket-sized wallets remain extremely popular to this day.