brain teaser puzzle 20pcs unlock interlock game iq test wooden toy 3d unlock interlock puzzle magic ball brain teaser toy puzzles for adults  features:<br> ●the puzzles look simple,but contain lots of mysteries. they are easy to disassemble but difficult to assemble.<br> ●train brains.it can make your brain sharper, develop intelligence, challenge your mind and patience.<br> ●have parties.take this set of brain teaser to share with your friends, families or colleagues.<br> ●these puzzles can get children away from phones or other electric device.<br> package include: <br> 16 x metal puzzle <br> 4 x wooden 3d puzzle <br> <b>cautions:</b><br> 1.children must be used it under the adult's tutelage.<br> 2.do not drop them on the floor or the desk.<br> 3.do not play with them if there is any issue.<br> 4.do not keep the toy in the mouth to prevent children devour small parts in the toy.<br>