Carseats "Expire"? Why?

Factual Questions
21

[QUOTE=WhyNot]
I didn’t know until a few months ago when the last Doper asked why carseats have expiration dates, but sure enough, ours does!
[/QUOTE]

Doggone it, I tried searching, I swear!

22

You’re supposed to replace your bike helmet every couple of years too for the same reason.

23

[QUOTE=fessie]
Doggone it, I tried searching, I swear!
[/QUOTE]

'snot coming up on Search, don’t feel bad. I know it happened, dammit! The hamsters must be getting hungry again.