DIYSeed can be purchased at diyseed.net. DIYSeed is meant to be a cheap and private way to create your own backup from commonly available items. It claims to be indestructible and not easy to read without the associated templates.
Hard to screw this up!
Heat Stress Test
The paper template guide burned off immediately as expected.
The underlying data remained intact. And you could use a new template (pictured on right) to decode the data.
Corrosion Stress Test
The divots are quite clear and can be decoded with a (separate) transparent template placed on top of them.
Crush Stress Test
No data loss, though as the device becomes more deformed it becomes harder to put a template on top of it to read the data. In extreme cases you’d likely need to flatten out the device again to achieve legibility.