Approximately 400 plastic cubes that measure 1 cm3, have a mass of one gram, and displace one milliliter of water. There is an assortment of 10 colors. Packaged in a zip-lock baggie. Cubes can attach on several sides to form larger cubes or other objects. Ideally suited for demonstrating mathematical concepts, weighing Sonlight resource: https://www.sonlight.com/products/gram-centimeter-cubes-kit