Cuisenaire Rods come in 10 different sizes and colors; each color represents a different rod length that can be assigned its own numeric value or unit of measurement. Rods range from 1 cm to 10 cm in length. This classroom multi-pack (in trays) includes 444 plastic connecting rods, enough for 12 to 18 students. Size: 23.4 x 19.3 x 18.5 cm. Ages 4+.