Viproo&reg; 3D Wooden Puzzle Toy Brain Teaser Kongming Lock Jigsaw Puzzle Assembly Puzzle Toy Children's Creative Toy--Luban Ball Note: Please kindly ignore the "Estimated Delivery Date" above, packages usually take 7-14 days for delivery with tracking number, thank you for your support. Material: Wood; Function: Intelligence development Help children to cultivate attention, increase patience, build confidence and stimulate their interest in learning. Help the adult to improve the way of thinking, adjust the state of mind, enhance the ability of understanding and reduce the pressure of work. Help the old to maintain flexible fingers, active brain cells, delay brain ageing, and reduce the risk of developing alzheimer's disease.