QSTDGVPW Solar Crookes Radiometer Desktop Ornament Science Toy Windmill for Entrance Desk Blue

[Desktop Ornament]: The solar power Crookes radiometer is a nice addition to your home decoration, suitable for decorating the desk, table, shelf, cabinet, entrance, fireplace, office, bedroom, living room, etc [Principle]: Sun light energy vanes, when the sun shines, the black vane surface absorbs heat energy, and the white vane surface releases heat energy, that drives the vanes to rotate [Educational Science Toy]: The solar power Crookes radiometer is a nice physics teaching toy, under sunlight or strong irradiation, the vanes inside will automatically rotate [Nice Gift]: The Crookes radiometer is a nice gift choice for kids, family and friends on Christmas, birthdays, parties, festivals, housewarmings, etc [Premium Material]: The solar Crookes radiometer windmill is made of premium high boron glass, sturdy, not easy to break and crack, and ensures a long time to use Specification: Material: high boron glass Size Chart: Height 21cm/8.27inch Ball diameter 9cm/3.54inch Base diameter 8cm/3.15inch Package Includes: 1 Solar Crookes Radiometer Note: Please allow slightly errors 1-2cm/0.39-0.79inch differences due to manual measurement.