Description: Coming with multifunctional feature, it ensures it can cultivate children's thinking ability and hobbies. It can stimulate children's interest in learning and curiosity through DIY small production, and let children understand abstract knowledge. Undoubted that this product contributes to developing children's intellectual ability, innovative thinking, hands-on ability and helps children develop their interest in science because this model is an educational DIY toy. Made of plastic material, it is lightweight. The length of product is 10cm, the width is 7.6cm and the height is 2.9cm. Suitable for school, home, teaching accessories. Item Name: Experiment Set Material: Plastic,Electronic Component Battery: 2 x AA Batteries (Not Included) Suitable Age: Over 3 Years Old Features: Safe, Reliable, Creative Size Details: 10cm x 7.6cm x 2.9cm/3.94" x 2.99" x 1.14" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Experimental Principle: Use the principle of direct current to PN type semiconductor to produce the PEL frame effect on the node to realize cooling. Package Includes: 1 Set of Experiment Set