Ideal for metal lovers collections to fill your collection. The surface is satin-finished, the effect is amazing, with metallic luster, and easy to maintain, suitable for collection, teaching, play. Due to the nature of metals, some oxidation or corrosion due to humidity and storage may occur. Features - Color: Assorted. - Material: Wood, aluminum, copper, iron. - Size: 8x6x3.5cm / 3.14x2.36x1.38inch. - Excellent for physics classrooms. Density Cubes have a wide range of educational applications for all grade levels, including density investigation, and specific gravity exploration. - Due to the nature of metals, some oxidation or corrosion due to humidity and storage may occur. - Simply scuff any oxidation off to make cube - Designed to be used in an educational setting and are not fabricated using ultra high precision machining. - It can also be used as a daily collection, as a decoration. Package list: 1 x aluminum x iron x woodden x packing box