It's a clear plastic box about 6 in. long, 3 in. wide and about an inch deep.
I've used it a few times and it builds up a couple of millimeters of silver inside each time. Eventually, the silver will build up so much that the electrodes will short out but, at the rate I use fixer, that will be quite a while.
When it is full, the box will have to be cut open. It's a two-piece construction with holes in the top and sides for the liquid to circulate through. It is heat welded together. In order for somebody to get that ingot of silver out, they'll have to split the plastic open, essentially destroying it but figure that you paid $50 for it and you'll probably get several hundred dollars for the silver. A worthwhile sacrifice. You'll still have the transformer so you only need to buy a new collector box.
I'm not going to get rich off this but I'll be able to buy a couple cases of beer and still have plenty left over to buy more film with.