Cold water dyes for all natural fibers, Procion dyes are permanent, colorfast, & washable. They are the best dyes for all cellulose fibers including cotton, rayon, linen, hemp, flax, paper, reeds & wood. They can also be used for protein fibers, but Jacquard Acid Dyes are usually the dye of choice for protein fibers. The 42 colors can be used to create a range of colors varying from light pastels to deep, vibrant hues. They are economical to use, as 1 ounce can dye more than 5 yards of fabric or about 9 T-shirts. Procion dyes are considered non-toxic when used properly. As with any dye, the use of a dust mask and rubber gloves is recommended. These dyes can be used in many ways including printing, airbrushing, stamping, hand painting, batik, tie dye, gradation dyeing, vat dyeing, splatter painting, etc. Instuctions for tie-dyeing, tub dyeing, washing machine dyeing, printing & painting are included on the back of the free color chart. One jar contains 2/3 ounce.