JHB is right. I have 17 of these on my truck. Gas pipe 1/2", 3/4", 1" plus, PVC fittings, screws, anchors, plumbing 1/2 & 3/4 fittings, reefer fittings and locking caps, anchors, nuts washers side beam hangers ceiling plates, fuses time delays relays, small caps, large caps, i think you get the idea. I take the little yellow boxes out for the fuse and cap ones. I buy 10 packs of fuses and label the side with a black marker, so I can see which is which. The caps I leave in the boxes too. I made the mistake of taking the caps out at first, but the numbers rub and then I am not sure what they are for stocking purpose, it's just more frustrating. I set my shelves so they fit perfect without losing to much height. I get 3 in a row, but somehow get four in my back shelves, I really shove those in. I do break them once in a while, but they are so worth the 18 bucks, and it is unbelievable how much abuse they take before they are broken. Get the ones that are on the bottom of his picture, with the yellow locking hinges