Product Details HLK-RM04 is a new low-cost embedded UART-ETH-WIFI module (serial port - Ethernet - Wireless network). This product is an embedded module based on the universal serial interface network standard built-in TCP / IP protocol stack enabling the user serial port Ethernet wireless network (wifi) interface between the conversions. Through the HLK-RM04 module the traditional serial devices do not need to change any configuration; data can be transmitted through the Internet network. Provide a quick solution for the users serial devices to transfer data via Ethernet. CD: http://m5.img.dxcdn.com/CDDriver/CD/sku.215334.zip