Hello!

This is a cover for a GM328A Transistor Tester - One of it's variants (compare the one you have with the one I posted here).

The design requires 3 additional components:

1.  Extend the lever on the transistor tester,
2.  include a power switch (optional, the unit shut down on it's own),
3.  4xM3 Insert nuts and screws (and soldering iron to heat them and insert them in the back cover).

I added labels + polarity for the terminals on the front cover, but my build plate ate them away (see STL files) - a smooth build plate + tuned up 1st layer will be beneficial here.

The Back cover needs to be printing facing down (to avoid using support).

After printing, 1-3 layers (0.3mm in the design) will block the screw holes, just pass a 3mm drill bit through and remove it. Its a design featured I saw on the "Maker's Muse" Channel, create sacrifice layer in order to not have sharp overhangs.

I printed mine in PLA, with 0.28mm layer height, 0.5mm line width, 0.4mm nozzle.

If you see something I can improve, please inform me, I will appreciate that and share\update here!

Enjoy!