The Incipio Delta iPhone 4 case is compatible with iPhone 4/S both Verizon and AT&T model. It is made of a high density polycarbonate and silicon material. The Delta offers a great deal of protection for the iPhone 4. The Incipio Delta case is made of two layers of silicone type material. The first layer of protection that goes on the iPhone like a rubberized skin. Second, it has a exo-skeleton type material surrounding the entire device. The exo-skeleton simply snaps over the other skin covering to form great protection. The two combined offer a great deal of support and protection for both the front and back of the iPhone 4.