Just about all electronics use a UART serial port with RX and TX pins for debugging, bootloading, programming, serial output, etc. But it's rare for a computer to have a serial port anymore. Thus, a serial cable is an essential part of any electrical engineer's toolkit.
This is a USB C to TTL serial cable with an FTDI FT232R usb/serial chip embedded in the head. It has a 6-pin socket at the end with 5V power and ground, and 3.3V logic (5V compatible) RX, TX, RTS and CTS. Useful whenever you want to communicate with a TTL serial device such as an Arduino Pro Mini or ESP breakout, and the pinout will match up exactly to any 'FTDI' 6-pin header.
The version we have is the 5V Power / 3V Logic. The data signals are at 3V output and the power line provides 5V. The logic pins are 5V-friendly so we suggest this for any product that needs FTDI cables and has 5V power usage or is 3V-logic friendly.
If you have a device that is running at 5V logic and power, this cable will work fine. If you want to tweak the voltages and signals a little, you should also check out the FTDI friend.