Keep your old kit as back up

[NorthernRaider]

I was suprised to find out that a fellow prepper I just exchanged E mails with was happily getting his eyes checked every 2 years and wisely buying two new pairs of specs and a pair of prescription shades.
BUT he was throwing away his older specs even though the script had hardly varied at all.

Turns out it never simply crossed his mind as such things often do for many of us. He never thought that one day he could get up to a world with no more opticians and dentists to replace his glasses or gnashers if he broke them.

He is now like me keeping his older shades and specs as spares in Bobs and caches because having slightly weak glasses is definately much better than having no glasses at all.

Also we are trying to work out wether heavier glass lenses are the best option or the light weight shatterproof plastic lens, cannot make our minds up.