Review on JBtek USB to TTL Serial Cable - Windows 8 Compatible Debugging Cable for Raspberry Pi USB Programming by Antonio Urbina

Great cable, 4 single pin connectors on the end. No documentation is included, just the cable. 1 star for that. There should have been at least a piece of paper to send you to the drivers website. Regarding the connections, the black wire seems to be solidly grounded and the red +5v, in my case white and green were 3.3v RX and TX respectively. but they seem to differ depending on which is which. I was able to determine this by simply prying off the blue USB port cover with a thumbnail or screwdriver to see which wire color was connected to which pinout on the chip board. If you're savvy with a soldering iron, you can also easily move the red 5V wire to an unused 3.3V power pinout should you need 3.3V power. Single pin connectors were easy to use. I connected pin 6 of the router to ground, pin 5 to RX and pin 2 to TX. The red power cord does not need to be connected. The rest of the procedure took some patience, but the cable worked like clockwork. Please note that the cable has drivers for OSX, Linux and Windows which you can download from the Prolific 2303 website. The cable appeared as /dev/usbserial on my Mac.