I ordered my M3W with one, and have since removed it. Damned hard to get to it, not much room in it anyway, and it severely limits passenger leg room. Nice idea, but not very useful in practice. I'm thinking of mounting it under the bonnet where it would be perhaps more practical to get to.
It's not square in any dimension, so sort of hard to communicate dimensions without a drawing - I can trace the outline of it with dimensions if anyone wants, as the box is currently out of the car. Dimensions are: Bottom - 9 1/8" at the front, 4 1/2" at the back, and 10 3/8" on one straight side, and 3 1/2 and 7 3/4 down the other side across about a 30 degree angle. Overall height is about 9 3/8" Front it angled back as per the pic.
It's a nicely made odd-shaped steel box with a aluminum door and lock. Other than that, not a lot to recommend it...
Last edited by truckin-on; 28/04/19 08:44 PM.