This hex dumbbell set features durability that simply can't be matched. It resists cracking and fading while protecting floors and equipment. Made from solid cast iron with a 6-sided anti-roll design and encased in virgin rubber, the set is as stylish as it is durable. Heads are securely fastened with a uniquely designed pin mechanism that means this equipment is about as low-maintenance as it gets. No spinning or loosening, either.