Pfaff 130 sewing mechanism ask? ? ? What is the purpose of that thing explicitly clipped around the presser...

What is the purpose of that thing explicitly clipped around the presser bar? I enjoy to take it sour every time I use the button hole attachment so, should I just acquire rid of it? Also it turns and moves up and down so I can't figure it out. I don't know if it would be worth buying the owners booklet on line if it doesn't describe what it's for or what it's call. What is it?
My Bose speaker and my neighbor.?
Answers:    Can you find a picture online that shows a Pfaff 130 with this piece on the presser foot bar? Sounds close to it may be part of some aftermarket complement...

Or take a appropriate photo and send it to Pfaff customer service and ask them what it is.

BTW, it's other a good model to have the guide, especially for a machine this antiquated. Missing oiling points when you're doing routine repairs can lead to some expensive repairs -- and the aged Pfaffs are such workhorses that it would be nice to take fastidiousness of the machine properly.