This Triple prism is a brand new and durable one. It is used to research therefraction and dispersion of the light， and make a thorough inquiry ofthe forming of the rainbow.A good present for children!Buy it now， and let your children enjoy the fun of light!Specifications:Prism Length: 1.97inch / 5cmSide Length: 1.18 inch / 3cmMaterial: optical glass， not plasticPackage Included:1 x 5cm Triple Prism + 1 Decent Gift Box