I’ve bought myself 2 types of tough durable ABS plastic boxes produced by Front Runner as part of my 4wd storage solution. The smaller is called a Gomo box and the larger is known as a Wolfpack or “ammo box”.
Both boxes are designed to be stackable with the lids made to interlock with the base of the box above it. 4 latches are integrated into the lid to securely lock on to the box.
These boxes are the typical choice for expedition use and seem to be well made and rugged. They are a great addition to your 4wd storage solution. A few of these boxes will get your gear to where you want it to go intact, with the only downside being that they are quite expensive. Overall I’m quite happy with my purchase. I may buy a few more once I determine my interior storage design.