I have had great luck with my Walmart special plastic (some kind of polymer or something) toolbox. Is just the right size to carry all the necessary tools to the junk yard. Long enough for my breaker bar and deep enough for my mini-sledge hammer.
Fits all my 1/2 drive sockets and wrenches.
Does not rust and has not cracked even during the coldest winter days.
It's yellow so I won't get shot by hunters.