I have been testing three of these bags/envelopes since September and can attest to they’re being of good quality. I have been using the 10.2 x 6” bag to keep cash and checks inside of a fireproof safe for double protection. I also have tested the larger file sized bags as they’re also waterproof and I have a second home in Panama (which has a very wet rain season) so I can also attest that these bags are waterproof and will keep documents dry. The material is durable and should last a very long time.
I did not test whether the bags were indeed fireproof but I saw that other customers posted videos on Amazon trying to unsuccessfully ignite them. I’ll just take their word for it.