DTECH FTDI USB to TTL Serial 3.3V Adapter Cable TX RX with 3 Pin Female Socket | eBay
CP2102 USB to TTL Serial Adapter Module for Lilypad / Arduino Pro Mini - Free shipping - DealExtreme
DFRobot RS232 to TTL Adapter - RobotShop
USB to TTL Adapter USB to Serial Converter for Development Projects Featuring Genuine FTDI USB UART IC FT232RL|Integrated Circuits| - AliExpress
CentIoT - USB to UART TTL Serial Adapter Module (CP2102 6PIN Black) for Industrial, Rs 135 /piece | ID: 21909314462
Amazon.com: diymore USB to TTL Serial Cable FTDI Original FT232 FT232RL Chipset Module RS232 6PIN Download Adapter 3.3V 5V for Arduino (Independent Dupont Head): Industrial & Scientific
Amazon.com: USB to TTL Adapter, USB to Serial Converter for Development Projects - Featuring Genuine FTDI USB UART IC 'FT232RL': Computers & Accessories