520 - Pro V Series - O-Ring Chain - 25 Feet - Solid bushings for longest possible wear - Reinforced rollers for greatest impact resistance

525 VO - Chain - 25 Feet - Solid bushings for longest possible wear - Reinforced rollers for greatest impact resistance

520 ERVT - Drive Chain - 120 Links - 520ERVT breaks down the concept of the original motocross chain (non o-ring) and adds the benefits of an x-ring - X-Ring helps keep your chain sealed with lubrication, limits dirt and mud from getting in-between the side plates, and only has 4 contact points with the plates which means less friction than the traditional O-Ring chain - More lightweight and longer chain life - By adjusting the materials, the 520ERVT is now 2% lighter and has a 15% longer lifespan, all while maintaining the tensile strength