Brain Teaser 12 Sets for Kids and Adults - All the coils and blocks are smooth and have endless play without getting hurt. The links are made from heavy-duty 4.5 that doesn’t easily bend or break even when thrown or stepped on. Players can’t force them open so there is no chance of cheating. It has also passed the International Toy Safety Standards and guarantees it’s top-notch quality.Classical Intellectual Disentanglement Toy Game rank from fairly simple to difficult specially designed for kids and adults to stimulate the potential of thinking, develop intelligence and practice manipulative ability.This Teasers Puzzle look simple, but contains lots of mysteries, definitely a good choice to exercise brains, improve problem solving abilities, relieve pressure at any leisure time or send as a gift to your friends.3D Coil Cast IQ Logic Educational Wire Chain Solutions - Great gift for boys, girls, men, and women ages 5 to 105. The perfect size makes it easy for small and large hands to play comfortably. Everyone can enjoy these unique novelty gifts, from children, teens, and adults. Can be played by a single player or a group. Give as gifts for birthdays, Halloween, Christmas, as well as party favors. Caution, not suitable for kids 5 years old and below.Brain teaser puzzle condenses with traditional Chinese culture and they are quite interesting to creative thinking and improve both your IQ and EQ.