Magical Rainbow Prism Optical Glass Crystal Pyramid Rectangular Pyramid Polyhedral Popularization Science Experiment Studying Student Tools Specifications: Material: K9 optical glass Height: 40 mm Attention: Height of 50mm, 60 mm, 80 mm and 100 mm are also available, please contact us. Thank you. Package Included: 1x pyramid prism Shipping Item will be shipped within 3 -5 days after your payment completed. We will ship the items to your address. Please make sure that your address is identical and correct. If you need to change the address, please tell us immediately after payment made. International shipping may be influenced by holidays, bad weather, emergency and so on. If in such unexpected conditions, the delivery time will even takes much longer time than that in normal condition. If you have special demand on shipping time, please inform us via message immediately after the order made.(DHL,Fedex,EMS,TNT,UPS,both available ,just needs some extra shipping fee) Feedback When you got the item ,Please check it first .If there was all fine and you are satisfied with our items and services,please leave a positive feedback with 5 stars. If you have any problems with our items or services, please feel free to contact us first before you leave negative feedback. We will do our best to solve any problems and provide you with the best customer services. Contact US Our working time is Beijing Time 8:00AM-18:00PM. If you have any question ,just leave me a message,I will reply at the first time when I am back to work. _x000D_