This is an EM standard card compatible with access control systems and electronic locks, such as those used by Rockman Japan and Lavish. It is a waterproof type with a credit/cash card size and a thickness of 0.9mm. Operation has been confirmed with dedicated reading devices. The front is blank, and the back is printed with a QR code. However, the content is a manufacturing management code, so the card number (UID) is not visible from the outside. It is intended for security purposes and will be shipped via anonymous delivery. Internal Chip: EM4200 Frequency: 125Khz *If you are unsure of compatibility with your device, please provide the model number, and we will investigate. Please feel free to ask any questions.