They are designed differently. Gascan S looks different.
EDIT: Calm down with the questions please. Since you're new here (welcome) why not browse the site and see what's here. It'll help pass the time until we all get a look at any new models.
Sorry to be so forward. Loving the site. The thing is, i used to work for Oakley. Back in the days of the real Oakley Classic eyewear. Still have close contacts to many staff member. But no one can get me pix. Just a little frustrating. There must be a way to find pix of the Small and the Pup. Im dying here..