I've had this for a bit but as I'd never needed it, it was still in the box.
Today with some cover stitching to do I thought I would use it. First panic, in a rush to get the packet open, about 6" by 4" ish, I couldn't see it for the amount of cardboard. I thought great, ordered it, never opened and the dam thing isn't in. When it dropped out I was rather underwhelmed, less than an inch square.
Anyway I put it where I wanted it, but it was moving around. So I ditched it and went back to what I was using before, three large plastic paper clips (promotional material while I was at work) stuck together and then stuck on the machine.
Worked a treat.