Oyster Shell Pellets vs. Oyster Shells

[Shadowglare]

I am fairly new to raising chickens. I was wondering what is the difference between Oyster Shell Pellets and regular Oyster Shells?
Is it ok to offer Oyster Shell Pellets as a temporary substitute for Oyster Shells?

 

[nuthatched]

It's the same stuff in different forms, like feed pellets or crumble.