Compressed cellulose sponges that expand in water! Before expanding, the sponge lays flat, providing an easy surface upon which to draw or stencil. It can be torn or cut with scissors or a knife to any shape or size. It's great for applying color to all sorts of fabrics and other surfaces. They hold a large amount of water and are tough and durable for craft use or cleaning purposes. 1/8" sheets spring to 5/8" thick when immersed in water. 4 sponges per package, measure 3x4".