All metal. The embroidery unit/cam stack is built in if it has the embroidery unit installed. There are no external cams. It does multiple stitches if it's operating correctly with the embroidery unit. They are not easy machines to work on and the parts cost an arm and a leg. If you are looking at purchasing one, make sure all components and necessary attachments like cords and controls are with the machine and that it is stitching all the embroidery stitches correctly. The embroidery unit is not fun to repair or remove and put back in. Belts alone will set you back $50-$75 each. Vintage Vikings and Pfaffs are some of the hardest machines to repair and there are very few people that will even touch them. I have about 15 hours of work into each of my Pfaffs and a good percentage of repair shops will not even look at your machine because the time necessary and parts cost too much.
If it doesn't have the embroidery unit, it's just a zigzag and straight stitch. You can tell by looking at the photo of one if it has the embroidery unit installed or not.
Last edited by Candace; 12-04-2012 at 04:46 PM.