Crystal gel skin cover is made of a smooth-feeling TPU (Thermoplastic Polyurethane) material. TPU is a mixture of plastic and silicone all in one, making it a semi-hard / semi-soft case. It is flexible, yet significantly durable at the same time; protecting your cell phone to the fullest. Unlike silicone cases, TPU crystal skin retains it's shape and repels dust. Crystal skin looks and fits like a hard case, however it is flexible with soft grip.