Owfeel Mini 13 Columns Plastic Abacus Soroban Arithmetic Mathematic Calculating Education Tool with Colorful Beads Traditional and functional arithmetic abacus for calculation. 13 colorful beads with 1 bead above and 4 beads below on each rod Used as a classical calculator in office or a nice gift for abacus collectors etc. Great education tool for teacher and mathematic tool for children. Well made plastic black frame, brown beads and bamboo rods.