BTW - these were made in sets for both Rotary and VS machines. The difference is the plates for the underbraider and shirr plate (used with ruffler). For the VS machines, they most often are used instead of the normal slide plate, for most rotaries, they mount to the bed of the machine.
you will often see boxes marked "rotary" while the sets for VS were normally just labeled "attachments" but that is not a rule, just a general observation. Often it's the shape/size of the underbaider and shirrplate that help identifiy what they may fit from pictures. Though often peices get mixed up together, if the owner had more than one machine.