Sustainably sourced. Royal & Langnickel offers the finest silk sponges famous for their high absorbency and tiny pores. Watercolor artists prefer silk sponges because of their unique characteristics. Ideal for use with Acrylics, Oils, Watercolours & Fabric Paints or dyes. Each sponge is individually hang sell packaged with care instructions written on the back. Approximately 3-1/2″ in size.