The standard plate
(sometimes called a curtain
or drapery plate) fastens with screws to the base of the machine.
The material that is to be ruffled goes over the top the plate and
the material that stays flat (called the flat panel) to which the
ruffle is attached goes under the plate. Because of the location
of the screws, the ruffles can only be sewed close to the edge of
the flat panel .
On the other hand, the optional dress plate
not attach to the base but is mounted on long rods that hinge from
holes in the upright part of the machine. This gives much more room
for the flat material and allows ruffles to be attached farther
from the edge of the flat panel as would be necessary in sewing
ruffles in tiers to a dress. If you buy the optional dress plate
you also get the standard plate.
The user can install either plate on the machine depending on which
is required. ( the standard plate does have the advantage of being
a bit more rigid than the dress plate, so if you are not doing ruffles
far from the edge you would probably want to use the standard plate.
) The machine can also sew ruffles without attaching to a flat panel.