These tires are made of a synthetic rubber that is commonly used in the automobile industry. These arent hard like the full nylons and not soft like the E-fires. These give you a good balance between ride comfort and longevity. Some of the biggest complaints of traditional nylons are road noise and rider ergonomics. These tires solves those issues, soft tires like the E-fires dont offer the lifespan that these do. The rounded profile allows you to hug corners and not lose traction while still maintining stablity.