When printing etchings, three felts are generally used. Closest to the paper, a thin absorbent felt called the Sizing Catcher. Next, the Forming Blanket, the thickest of the felts, acts as a cushion to cast the paper over the etching plate. It tends to be soft and resilient and is normally a blended felt (50% wool, 50% polyester.) It is most economical to purchase precut felts, or order custom felts by the full yard.