Do these protect against snakes?

They will serve as some protection, but they are not made for snake protection

No non-venomous snake (in North America) has teeth any where near long enough to get through this material. The only (only!) thing that would be of any concern would be very large pit vipers (read: big ol rattlers). Snakes that big are tremendously rare in the wild and, trust me, they do not want to tangle with you. Herpetologists that stomp into rattler country on purpose wear loose fitting long pants over regular ol hiking boots and carry a long stick. You are good to go!
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