Freeform pieces come in precision-cut 2 centimeter increments (2, 4, 6, 8 and 10 centimeters) with large 2 centimeter disks and bridges to support successful building and early math and metric system learning. Diameter of blocks varies. Typical set includes "Y" or forked pieces. Tree Blocks come in a colorful, cotton twill, drawstring sack with attractive logo block. 36 pieces per set. Ages 3 years and up.