Case for esp32 8 relay board designed for use as an amplifier/speaker switch. Design includes parameters for size and mounting post spacing so should be adaptable if your relay board has different dimensions. M4 and M3 screws w/ threaded inserts are used for mounting the board and securing the case.

The project pictured here is used in my smart home to automatically swap my main speakers between different amplifiers when changing from music listening to surround cinema mode. Be careful to implement controls so you don't let the smoke out :)