EM18 RFID Reader
EM18 is a RFID reader which is used to read RFID tags of frequency 125 kHz.
After reading tags, it transmits unique ID serially to the PC or microcontroller using UART communication or Wiegand format on respective pins.
EM18 RFID reader reads the data from RFID tags which contains stored ID which is of 12 bytes. 
EM18 RFID reader doesn’t require line-of-sight. Also, it has identification range which is short i.e. in few centimeters.
 
Key attributes
Item: RFID Reader Modules EM-18
Encoding: Manchester 64-bit, Modules64
Frequency : 125KHz
Printing Option: Printing/Serial numbers ect.
Card format: EM4001 or compatible
Size: 32*32*8mm(±0.4mm)
Certificate: RoHS
Interface: TTL232/WG26
Power Supply: 5V DC
Protocol:    ISO 14443A
Reading distanc:    5~8cm
Communication protocol: UART
Baud rate: 9600, 8, N, 1
 
Resources: 
1. EM-18 RFID Reader Module Interfaced With Arduino Uno
2. RFID Reader EM18 Guide with Arduino Interfacing