There is a lot of confusion between carbon fiber and aramid fiber, but they are not the same material. The confusion is understandable - both are man-made, modern composite materials widely used for their strength and lightness, and both come from the same material family.
However, carbon fiber is an electrical conductor, which means it can interfere with cell phone signal reception. Aramid fibers, on the other hand, are non-conductive and will not affect WiFi, GPS or phone service. Additionally, while carbon fiber is strong and stiff, it's also brittle, which means it may protect your phone from drops and impacts but may crack on impact.
