Snail Identification

[Benzo]

Hello All,

My tank has been running for about 4 months now. I want to add some snails that I got from my cousin's tank but not sure if I should or not since I don't know what they're called and can't find any info about them if it's safe. He said he got them from San Francisco bay. I think they're called Ilyanassa Obsoleta but not sure. Any help is really appreciated.

Thanks