KidWind Wind Turbine Hub, three-pack of 12-hole crimping hubs, made from recycled plastic, allows you to turn any DC generator into a wind turbine, Diameter: 2.25 in, Maximum number of dowels: 12, Size of shaft hub press fits onto: 2 mm
Mini Density cube set,Study Several Properties of Matter. Learn about density, mass, volume, buoynacy, specific gravity, and flotation while experimenting with real-world materials. Made from commonly used aluminum, copper, steel, brass, and zinc.