Alzilla is right, if you want to sew two layers of 9 oz, a cb 3200 would be ideal. The main problem is getting proper thread tension, as most of these lighter class cylinder arm machines will only handle 138 effectively. 207 will act up at the worst time every time. I have a Techsew 3800, which is now a Cowboy 3200. Most parts from any 441 clone will fit, and they have the same punch power as a full size 441.