Delightful, creative building toy. Exercise agile young minds in a fun manipulative way. Each disk interlocks with any other in 8 positions. Makes any number of shapes. Long strings can even be formed into curves! Use for math, phonics, and chip-trading games. Make mobiles, shapes and figures. 8 colors. Easy for tutor; easy for learner. Suggestions for use included. 11/16" diameter.