Abstract: A pair of triangular cross-section racks are maintained spaced apart from but parallel to one another by a plurality of rods slidably and retainingly engaging the racks to form a supporting frame. A plurality of diamond shaped apertures are disposed within the opposed face of each of the pair of racks to retainingly receive and support opposed corners of sheet materials mounted upon the pair of racks. The slidably engaging rods permit the spacing intermediate the racks to be adjusted to accommodate the width of the supported sheet materials and the diamond shaped apertures accommodate sheet materials of different thicknesses. Means are also described for sealingly enveloping a frame loaded with hygienically cleaned pieces of sheet material.