American Paper Optics made a page showing the differences between their glasses and some knock offs. https://www.eclipseglasses.com/pages/safety https://www.ecl

American Paper Optics made a page showing the differences between their glasses and some knock offs. https://www.eclipseglasses.com/pages/safety https://www.eclipseglasses.com/pages/safety This doesn't mean the shape can't also be copied perfectly though, so I'm not sure if it's helpful or just doing even more harm.