Micro-controller case, should fit any 2.54 mm pitch micro-controller like ESP 32, ESP 8266 or Arduino Nano.

BOM:

• QTY 2 M3 X 20 Wood Screw (https://www.aliexpress.com/item/32798366511.html)
• QTY 2 M3 X 20 Button Head Machine Screw (https://www.aliexpress.com/item/32798146322.html)
• QTY 2 M3 X 6 X 5.3 Embedded Nut (old link no longer works - possible substitution M3 X D5 X L6) https://www.aliexpress.com/item/4000232858343.html
• QTY 1 Switch Momentary On 6 X 6 X 11
• QTY 1 Micro Controller

Note: the large opening is provisioned for a MAX9814 microphone amp with AGC for audio inputs - to secure use the filament heat stake method described in my other projects. I'm trying a new method where one end of the heat stake is concealed, preheat the end before inserting and then squish it into the hole. The opening has a spherical profile inside which should hold the heat stake captive.