Why you need this: 1, In most case there have big voltage difference between PC and it's peripheral equipment's ground, it will lead the equipment working not stable even damaged the equipment and the PC , you need to isolation it to make everything safety.
2, The PC's switch power supply have big noise, you need to isolation it to prevent the noise entery your device.
3, Most USB to UART convertor have a fixed level (3.3V or 5V) , it's may not match to your device's request, use this convertor can be provide same level as your device.
4, You need a very small size and weight converter to carry it, he will travel with you anywhere.
5, USB to UART, USB to RS-232 (Female and Male connector), USB to RS-485RS-422, a set of equipment to meet all the needs of engineers commonly used.
6, Rich LED indication, work status at a glance.
7, Very soft wire with a length of 1 meter to meet all work scenarios\
Recommend purchase link:https://www.ebay.com/itm/323854073372