The USB to TTL converter is build by PL2303 chip , its designed for mobile and embedded solutions in mind, with very small power dissipation.
Cable length : 1M (3.2ft)
Black pin : GND (Ground voltage)
Red pin : VCC (3.3-5V)
Green pin : TXD (Transmit asynchronous data)
White pin : RXD (Receive asynchronous data)