Usage Tips:[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 better use it in your . After multiple processes, product quality can be 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 and other items for easy use and avoiding loss. The volume of the key tag is 3.3x2.9x0.6cm, which is small in size and convenient to carry. It can be easily put in pockets and backpacks. -shaped appearance makes it better for daily use. [TK4100 Chip] The type of RFID sensor ID card chip is TK4100, working frequency: 125Khz, you can the appropriate access card according to your needs. Compatible with standard ID access devices or ID . Each chip has own ID, which is stored in the chip and printed on the back of the to security. [Read Only & Easy to Read] The chip is write- and 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 reader, and the reading distance is 0-10cm. [Good Helper for Access Control System] RFID key can be used in a of , suitable for access control, hotel locks, employee attendance, school campus visits, identity recognition, security , parking lot access, attendance , etc. It can be used in 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 colour:blue, red Package Contents: 50 x 125Khz RFID Card Tags Only the above package content, other are not included. Note: Light and different displays may cause the color of the item in the a little different from the real . The measurement allowed error is +/- 1-3cm.