I created this USB SD card reader caddy to hold up to 20 USB card readers.

I made it to store SD card readers for my students to use at school.

The specific model this holds is the Kingston MobileLite Plus SD Reader.

It has raised numbers (1 - 20) next to each hole - I went over these with a black marker, which was easy.

I suppose you could use it to hold USB memory sticks, or even USB cable ends.