Will Kiinde bags still be ok to use after 3 years?

Kayla • 12/30/16❤️ 1/20/18 💑 12/12/19💙

Can anyone tell me, we have kiinde bags from when our daughter was born 3 years ago, would they still be ok to use to pump into? They’ve been in our lower level in a box and a bag (we have a bilevel house). I don’t see any expiration dates on them.