Continental Gatorskin Tires feature puncture resistant casing and wear optimized tread. Highly puncture-resistant casing with Duraskin sidewall protection High mileage carbon-black tread compound Continental has changed the name of the Ultra Gatorskin to Gatorskin. No changes have been made to the tires other than the label For Hardshell Option: Continental Gator Hardshell Tires are designed with Hardshell-ProTection to provide puncture protection and high mileage. A wider PolyX Breaker and a three ply carcass makes it a these hardshell tires puncture-resistant. High-mileage, carbon-black tread compound Duraskin sidewall protection, in addition to Hardshell features, provides a durable, high-performance tire suited to athletic urban riding styles Hardshell protection consists of casing-ply overlap covering more of the sidewall than normal, plus an extra-wide PolyX breaker