Box for miniR4M

Enclosure to enable a Sonoff miniR4M to be used in line.
A hole in the lid allows access to the manual switch on the top of the miniR4M, and also enables a view of the power led.
If you need to join earths you'll need a chocolate-block connector; a slot to retain this is provided in the design.
Cables can be retained by cable ties attached to loops inside the box.
Box is closed by 4 M3 melt-in threaded inserts, one in each corner and 4 M3 screws through the lid that need to be about 12mm long.