This simple Snap-on USB Dongle Case / Enclosure is an inexpensive way to turn a bare PCB into a more durable project (as long as the PCB design shape is under you control). For much less than it would cost to get a custom 3D printed case, and way way less than injection molding!

This case seems to be designed for USB power monitoring boards kinda like this one. It's made of grey translucent plastic, so you can have a small TFT or OLED or LEDs. There's three pieces, two snap over the PCB to capture it in place and one can be used as a USB A port cap. We also like there's a button lever - use a low cost tactile switch as a reset button or mode switcher!

While the original was intended for use with a USB A plug and socket, you could probably be flexible with what connectors you're using as long as they're smaller. For example, we designed a board with a USB A plug on one end, and terminal blocks/breakout pads on the other.

This case is great if you want to protect your USB dongle from everyday usage, but note that it is not waterproof or weatherproof.

No boards, cables, or accessories are included. You'll need to design your PCB to a specific shape for it to fit snuggly inside - we used the diagram below plus calipers to get something satisfactory with only one revision tweak.

Play video: #NewProducts 4/23/25 Feat. USB C PD to 2.1mm Cable with Selectable Voltage Button! @adafruit