KidWind Dowel, Recommended for College, High School, and Middle School Science, Diameter: 0.25 in, Length: 5 in, used for designing and testing wind turbine blades, and they fit into the KidWind Wind Turbine Hub, D100
Drilled Ball Set, 1inch Diameter, set of 12, erfect for conducting own pendulum experiments, 3mm hole is drilled down the center of each ball, Comes in a plastic container with foam padding to hold the drilled balls firmly in place