The soroban is a calculating tool developed in Japan. Expand your and your children calculation skills with this very useful and fun abacus. soroban是在日本開(kāi)發(fā)的計(jì)算工具。展開(kāi)你和你的孩子的計(jì)算能力，這非常有用和有趣的算盤(pán)。