This is a compact 3D printed case designed for the popular high-precision frequency counter—the 1Hz to 50MHz full frequency range crystal tester.

It can effectively protect the circuit board while providing a clean and professional appearance for desktop or fixed installation.

Compatible with this device:

https://s.click.aliexpress.com/e/_c2zdUZaN

An additional 9V battery interface can also be added if needed:

https://s.click.aliexpress.com/e/_c4P1T8Hf