What type of snails to give to figure 8 puffer

[amazon]

Can anyone tell me what type of snails I should get to feed my figure 8 puffer.
Ive been giving it blood worms aswell as frozen shrimp with shell but I need to get some snails with the shell and I dont know where to get them or what type of snails I should be buying

 

[Dwarfs]

Most pet/fish stores will give you pond snails. They reproduce very quickly and my dwarf puffers love them