Fully enclosed Solid steel, but with some possible gap for water to leak in.
That's what I did. Nearly perfect product, used it for keys, and sometimes anything else. If it only had rubber seal around the opening, then it be waterproof, the back needs to get waterproof too with those holes, but it's good enough. The star was removed because the lack of full waterproof, better for indoors in my opinion. It gets good rating for being ridiculously hard all over.










