You mean the clip that runs over and over in the back ground? I can't see enough of it to identify, but there were lots of industrial treadles with presser bar knee lift (the metal rod in the back of the machine). I've also seen early treadle zigzaggers with the parts that control the swing needle parts running externally along the machine body both in the front and in the back. This looks like a straight stitcher though. It could be a Singer, other brands I've seen have been Gritzner, Mundlos, and lots of others. I guess it's an industrial model, not a domestic like the 101.