My brother liked my gridfinity boxes and wanted a custom size one for his automotive electrical connectors. 

I copied the basic design from this one that I have printed before:

https://www.printables.com/model/495142-rugged-gridfinity-box-parametric

Printed on my Voron 350mm using 1kg of black Eligoo Rapid PLA+ 20% infill and no supports. You will also need 6 M3x30 screws for the hinges and latches