Incipio DualPro Hard Shell Case with Silicone Core for Nokia Lumia 931 - Retail Packaging - Black/Black DualPro features design innovation at its best! With a plutonium plastic exterior embedded in a shock absorbing silicone core, DualPro provides sturdy protection without sacrificing style. Rigid Plextonium shell with impact absorbing silicone core Innovative hybrid design Protection with style 2 layers of defense