The lock may looks simple, but it contains lots of mysteries. Fine way to improve your divergent thinking and patience.Features:The lock became a popular toy for all, thanks to its functions of mind-body relaxing, intelligence boosting and making fingers more flexible.Training your IQ and relaxing your body and brain- helping you understand the Chinese culture better.The most representative of classical intelligence toys.Non-toxic and harmless wood material, old people and children can play, can develop intelligence to prevents dementia.It helps to fully develop the right brain, improve the way of thinking, and regulate the state of mind.Specifications:Material: woodenType: 1,2,3,4,5,6,7 (optional)Package size: 100 100 100mm / 3.9 3.9 3.9inPackage weight: 80g / 2.8ouncePacking List:1 Kong-Ming Lock