Zooshine 18 Sets Metal Brain Puzzles Teasers IQ Toys,Metal Puzzles Games for Adults Kids 18 Sets different styles metal puzzles rank from easy to difficulty Very good parent-child games,party games,office toys for relax and killing time Good for creative thinking and improve your patience, intelligence, IQ & EQ Metal brain teaser condenses with Chinese classical culture, quite interesting Tips: If you want more fun & Challenge,please DO NOT refer to the solution "Challenge Guide".The really most interesting thing is exploring it,but not the result