Package includes 1 x glass light mill Key features Size: about 13.00X8.00X8.00 cm (5.11X3.14X3.14 inch), compact desktop size suitable for classroom tables and display shelves. Material: borosilicate glass for clear visibility and durable performance. Color: yellow tint to help detect and demonstrate the presence of sunlight. Function: internal vanes rotate automatically when placed in direct sun or irradiated with an incandescent lamp, providing a clear visual demonstration of light energy in motion. Construction: solid glass body, sturdy and resistant to deformation and breakage under normal use. Why you need this product Clear, handson demonstration of light driven motion for physics and solar energy lessons. Durable glass construction provides longlasting clarity so students and observers can see the internal vanes and motion without obstruction. Compact size and attractive design make it useful both as a teaching aid and a desktop decoration that illustrates a scientific principle. What makes it stand out borosilicate glass offers better transparency and heat resistance compared to ordinary glass, making the internal process easy to observe. Yellow tint emphasizes sunlight detection, helping observers quickly see when the device is active. Simple operation requires only a light source so it is ready to use in a variety of learning environments. Typical applications Classroom physics demonstrations to show energy conversion and the effects of light on motion. Solar energy experiments where students compare rotation speed under sunlight and artificial lighting. Office or home desktop display that doubles as an educational conversation piece. Notes on use Place in direct sunlight or shine an incandescent lamp on the device to start rotation. Handle with care when moving or cleaning to preserve the glass finish.