Review on Ajax Scientific Optical Equilateral Length: Precise Measuring Tool for Optical Experiments by Todd Phillips

I bought this as a supplement. The product was well packaged and had no noticeable flaws. My reason for only giving this prism three stars is that it shows no refraction I have tried putting it in natural sunlight. I've tried mounting it on a glossy black surface and on top of a mirror. Still no luck. The ones we used in school 45 years ago ALL featured vivid rainbows, especially in natural sunlight. Although this version makes a good paperweight :)