The original Color Catchers were white untreated terry cloth. You could reuse them until they became dark gray with color. Many simply bleached them clean and reused. The catcher was the size and looked like a regular bath cloth (wash rag). Any untreated white cotton fabric will work. The ready for dye cotton fabric available now will work the same as the paper dye catchers. But that fabric is costly but you can use a large piece for a big quilt.