The Radix One Black Steel is an ultra-thin replacement to the standard bi-fold wallet, with RFID blocking capabilities built into the material. It is designed to carry 4-10 cards between the heavy gauge steel plates and is held together by a durable silicone band. Cash can be held by the band much like a money clip. To increase the capacity for carrying cash, just unhook one of the clips on the back of the steel plate. Patent protected.