This adapter board is designed to work with the USB 3 Hub board, make it easily to connect the USB 3 hub's downstream port to a USB Type C device that requires USB 3 data speed. 

Specifications: 

• Dimension: 9.8*11.0mm
• length with USB C connector: 22mm
• PCB thickness: 0.8mm
• Interface: USB 3 / USB 2

Connection guide: 

Notes: 

1. carefully check the connection before you power on your device, wrong connection may cause your device damaged. 
2. use tools to verify if the device is working under USB 3 or USB 2, I used a USB C SSD in above example, the tool shows it works under USB 3
   
   

PS: So far I manually solder this adapter at home, not sure how many people would buy it, so the board might look ugly. I test every of them before sending out. 

For any questions, feel free to contact me via email.