Topbox Weight

[Mark65]

So after my mistake with my D lock falling of the bike and the weight of my laptop and dinner and other things jammed in the Kreiga I've remounted the Kappa K400 on my bike.
I've mounted it onto the plate I bought which has a bigger surface area, I've used M8 flanged bolts on M8x25mm washers, all stainless and it feels solid, I've left the Kreiga straps on there as I can then strap that on the seat as well, my question is has anyone had a box brake off of crack using this method, I know the box is the budget end but if it works OK I make look at alloy ones. I just don't want any stuff falling of and causing an accident, in hindsight the Kreiga alloy cam straps I have would have been the better choice but I can fit everything in this box, I could even go smaller.
Thanks for any input
Mark

[Mark65]

And

[cooltshirt]

In the real world it will probably be fine. But if it was mine I'd consider a bar or similar between the bolts to further spread the load.

[MisterDavey]

I think it'll be perfectly OK.
You've used decent sized washer to spread the load.
Also, I have a Monokey top box, and Monokey only used two little stumps and the latch to keep it in place. So what you've done is pretty good.

[Mark65]

Thanks, there 25mm under as well but I've just ordered a few 40mm for the two on top that will fit