This is PL2303 PL2303HX USB To TTL(Serial) Converter Module – 5 Pin. Adopt imported controller RS232 TTL, which can stabilize the flash with high-speed 500mA self-recovery fuse for protection.
 
Two data transmission indicator can monitor data transfer status in real-time. Reserve 3.3V and 5V pin interface, easy for DDWRT of different voltage system that needs power.
 
The entire board is coated by a high quality transparent heat-shrinkable sleeve, making the PCB in insulation state from outside, so that the board won’t be burnt down by a material shortcut.