These key fobs are designed with different size and shapes.They are typically used as an employee badge for door access or permit to areas such as public transportation,apartment and hotel rooms,e-payment, and more.We can provide RFID key fob 13.56MHz ( the most popular is Mifare RFID key fob ), RFID key fob LF(125Khz), UHF RFID key fobs and Combi RFID key fobs.