I would add my recommendation for Really Useful Boxes; they are not the cheapest around, but their quality is first rate whereas cheaper ones are usually disappointing. I have scores of the things, from very small to quite large; the small and medium ones are used for socket screws (of which I have several lifetimes' supply), cutting tips, milling cutters, bearings and the like. Larger ones are mainly for storing metal offcuts; they seem to have survived several years' use in that without apparent damage, and the amount I put in each is limited more by my ability to hump them around than their intrinsic strength.
David