Flexible rock mold Use with casting plaster to make rock formations Combine with other rock molds to create hundreds of unique combinations Mold size: 5" x 7" Woodland Scenics Rock Molds are durable, flexible, reusable and well detailed. Use Lightweight Hydrocal (WOOC1201) to cast small boulders, rock outcroppings, top rocks for fields and creeks, or entire rock faces. Color with Earth Colors Liquid Pigments (WOOC1215).