The stronger the light, the faster it rotates. If possible, place it in a window sill or other place with strong light. It is made of glass and is therefore fragile. It is suitable for children over 13 years. It is a gift, send it to our or family. love it! When the radiometer is placed in the sun, the wings continue to rotate. Place it in the or living room is very good., Manufacturer: Wresetly