Here is an antique 1878 cast iron hand flutter tool made by Shepard Hardware in Buffalo New York. Patented in 1878 and 1880. The base measures 7" long x 4" wide. With the handle in place on top of the base, the piece is 6" tall. The cast iron handle measures 4" wide and is stamped with the 1880 patent date. It has a removable cast iron heating plate under the fluted lid section.
The fluter rocker-like device is a specialized kind of "sad iron", used to press the fluted ruffles on linen cuffs and collars and other trim.
Made from cast iron, the fluter would have been heated on coals in the fireplace hearth. The collar or cuff to be ironed would be moistened and laid over the grooved base. Then the heated iron would be rocked over the cloth and the linen would be perfectly pressed with rows of narrow flutes or pleats.