9cm Optical Glass Triple Triangular Prism Physics Teaching Light Spectrum a

Model: Triangular Prism. teaching children to understand the magic world. 1 x Triple Prism. Original 44mm Stainless Steel Watch Case For Seagull ST3600/ST3621 ETA 6497/6498. Seven-color reflects sunlight and teach children to explore the mysteries of light to stimulate a child's thirst for knowledge.

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