Custom Dual Frequency RFID Chip Keyfob is made of ABS material with rfid chip and antenna . It will be durable and injection ABS case then sealing rfid chip under ultrasonic machine without any space sideview so that you can use them in out-door harsh environment and waterproof ,This type rfid keyfob has enough space and can set up dual frequency rfid inside , you can check with your project and chose correctly rfid chip let us to do ,such as 13.56mhz with 125khz , 13.56mhz with 860-960mhz or 125khz with 860-960mhz ,etc .