• synthetic material
• Sensory :it can help develop memory, reaction skills and problem-solving skills, Sorting
• Building ring stacker:bright colors and chunky size make it easy to to grasp, easy for your playing, Stacking
• Shape sorter stacker:there is a hole of each circle, can set these rings on the stick by the size of rings or other way their like​, Busy Board
• stacking :help develop memory skills and stimulate curiosity, boost confidence as they complete the game, Stacking Tower
• geometric stacker:these feature different color and shape design, manufactured for training sensory ability,Early Educational