[Waterproof ABS Material] The RFID key tag is made of high-quality ABS material, the shell is strong and durable, has good waterproof, shockproof and anti-corrosion performance, so that you can use it better in your . After multiple processes, the product quality can be well guaranteed. The red and blue colors give you more choices. [Comes with a portable key ring] Each tag is equipped with a key ring, which can be hung on keys and other items for easy use and to avoid loss. The volume of the key tag is 3.3x2.9x0.6 cm, which is small in size and convenient to carry. It can be put into pockets and backpacks. The format makes it better for daily use. [TK4100 chip] The type of RFID sensor ID card chip is TK4100, working frequency: 125Khz, you can choose the appropriate access card according to your needs. Compatible with standard ID access devices or ID . Each chip has its own ID, which is stored in the chip and on the back of the label for security. [Read-only & easy to read] cannot be programmed! It does not support and is not compatible with UHF and encrypted , such as , Radio, Cobra, , APCiK, Indala, Isonas, , , etc. The waterproof RFID key tag is suitable for 125KHZ card readers, and the reading distance is 0-10 cm. [Good aids for access control systems] RFID key tag can be used in a variety of , suitable for access control, hotel locks, employee attendance, school campus visits, identity recognition, security , parking lot access, attendance registration , etc. It can be used in any situation where an access control system is needed, such as offices, homes, schools, communities, etc. Support: Read-only, not writable. Working frequency: 125KHZ Size: 29x33x6mm Material: ABS Color: blue, red Package content: 50 pcs Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3 cm.