My experience with so called waterproof storage boxes is that they are far from being waterproof. Especially the plastic ones. So I was very sceptical about the claim that this metal one was, because firstly you have to assemble it and secondly how are the sides going to form a seal against the weather. The storage box is to be used outside to store tennis equipment. The package is very heavy and really needs two people to carry it. The pieces are clearly marked and the assembly instructions in pictures are reasonable easy to follow. The metal sides are coated with a plastic film which is best to leave on as trying to peel them off is too much work. Tools that were required were a posi screwdriver and a M4 socket or spanner and an adjustable spanner. Your hand will ache with the number of screws required to assmble the box! It took two of us about 4 hours to assemble the box. I left the box empty and waited for it to rain to see how waterproof it was. With rain that just fell the lid keeps it dry. With driving rain water does entry via the ridges in the side pieces but I think it is designed for the water to run down the inside corners and out through drainage gaps at the bottom of each corner. It is probably best not to store things right into the corners and instead leave a gap. Still sceptical about it but it's better than what we have at the moment.
Once built the box is really sturdy, waterproof (so far) and big enough to fit all of my sofa-set cushions. As a lot of people said, it takes absolutely ages to build, the small bolts are very fiddly, and the instructions aren't very clear. You will definitely need 2 people for at least some of the build. I thought the piston rods were faulty as they're incredibly stiff, but customer services came back with this which I'm pasting in case it helps others: [Before attaching] use your full strength to press down on each rod with one end on the ground. After installing the rods, open and close the lid with two people to simultaneously apply pressure at the top of each gas rod. After a few reciprocating movements, you can achieve single-handed opening and closing.
Great purchase.