Crayon Rocks are simply the best colouring tool for young children! They are vibrantly coloured and make beautifully textured art work similar to oil pastels. These all natural soy wax crayons are made from USA grown soybeans and coloured with natural mineral powders. They are designed to strengthen the tripod grip muscles in young children, preparing fingers and hands for handwriting. The shape allows small fingers to apply colour in large, wide strokes. Used by occupational therapists and preschool teachers to develop fine motor skills. Crayon Rocks are non-toxic and conform to ASTM D 4236, EN71 and CPSIA. Length of each crayon is approximately 3.2 x 1.9 cm. WARNING: Choking Hazard. Not for children under 3 years. Use with appropriate supervision.