Get to know the "Core 4"

Get to know the "Core 4"

Are your eclipse glasses safe? Let's check them out using "The Core 4".

Solar eclipses are among the most spectacular cosmic phenomena visible from Earth, but they have to be enjoyed safely. Because observing an eclipse involves looking at the Sun, it’s essential that you only do so with safe solar viewing products.

So how do you know if the glasses you have are safe and ready to use? We get this question so much that we've come up with our own 4 step method you can quickly use to see if your glasses are safe! We call these steps "The Core 4".

Before anything, you want to make sure that you purchased or received your eclipse glasses from a reputable American vendor


1) Make sure that your eclipse glasses have been made by a trusted American manufacturer. Our American Paper Optics info is printed on the back of all our eclipse glasses, and we are on the American Astronomical Society (AAS) approved vendor list. In fact, we make eclipse glasses for the AAS and NASA. 

2) Our glasses have a silvery front lens and a black back lens. Make sure the lenses are in good shape and not torn or punctured. 

3) Your glasses need to be ISO certifiedYou can tell if a pair of solar eclipse glasses meet the standards if they are labeled ISO 12312-2. We send our eclipse glasses to specialized labs to make sure they comply with the International Organization for Standardization (ISO) 12312-2 safety specifications.

4) Finally, the back of your glasses should have user instructions from the manufacturer on how to safely use your eclipse glasses. 


Unfortunately, numerous vendors sell eclipse glasses with the ISO certification that haven’t actually been tested and certified. These vendors have also been known to add us (American Paper Optics) as the manufacturer of their glasses, which is also false. *Example below shows a pair of counterfeit eclipse glasses. 

When it comes to safety, it's just not worth taking the risk. The only way to be completely 100% sure that your eclipse glasses are safe is to buy them from us (American Paper Optics) at