Review on Enhancing Science Education with Rainbow Symphony Diffraction Grating Slides by Ryan Turner

That's why I bought it. I have a few of these in my wallet. It's always cool when you hang out with your nerd friends to pull one out and show them the spectrum of lightbulbs in the restaurant you're eating at. You can always spot cheap lightbulbs because they don't have a continuous spectrum. Then when I ask them if they want it and give it to them, they are always amazing.