I have a Pfaff Quilt Expression 2.0, not a 4.0, but I think they pretty much take the same feet. I have only been doing fmq for about a year, and have the 2 fmq feet by Pfaff for my machine. I would like to try ruler work, I have an older Handiquilter frame, and found this foot on ebay. I think my son, a welder, could build up the food with solder, so I could use it for ruler work, but I would like to know if anyone has tried this foot on their machine. It says it fits my machine, but I would like to know if anyone has tried it first, before purchasing.