Review on Amlong Crystal Triangular Teaching Photography Science Education at Optics by Dan Chunn

Would I buy again. There was little evidence of bubbles or cracking when a bright green laser beam was passed through the glass, unlike another prism I received recently which was riddled with bubbles and other tiny imperfections. Here the rays appeared as dots rather than ever-changing blurred areas depending on the specific optical path. I'd say pretty good quality for a cheap prism. When positioned correctly, it casts a nice, reasonably sized rainbow flag onto a flat wall. Great if that's what you're looking for.