Are its innards actually exposed like that? I just bought a simple johnson controller, and it has a grey cover on it. I needed it quickly, so I ordered from MoreBeer. That one works by interrupting the power supply at the plug---wonder how this 4 stage deal works.
Even if you had to put electrical tape over the contacts, it could turn out to be a great bargain. I think the multistage units are for kicking on additional fans or cooling units depending on how far off set temp you get. I could be way wrong but I think you can use this as a simple on/off controller. The one detail not listed is whether this is for cooling (close on rise) or heating (close on fall). Maybe it's both given the "4 stage" label.