So…um…what did I just get?

Won an auction yesterday for what I thought/hoped was a OO gage Thomas set. Brought blind so I had no idea for sure. Well, picked up today and this is what I now own, for the grand total of £3. The controller powers up, but may need a little work before Thomas will actually move. He himself needs a little tlc for the eyes, but mostly he’s in good condition. So what kit is this. I can see it’s Bachmann, but Google isn’t giving much to go on. I think it’s possibly G gage? But this is a little out of my knowledge base. Any ideas?