The 520 size has been upgraded from VX2 to VX3! The operability has been further improved by increasing the rigidity! Exhilarating riding with light operability. High performance & best value. Equipped with DID patented X-Ring as standard equipment, it achieves low friction and long life. Suitable for a wide range of vehicles. Designed exclusively for each size, the basic performance of the chain has been greatly improved, making it suitable for a wide range of vehicle models. A higher level of security brings out the enjoyment of riding. Contributes to improved fuel efficiency by reducing friction. Compared to genuine O-ring chains, the DID patented X-ring reduces sliding resistance and contributes to smooth running and improved fuel efficiency. Amazing long life of X-ring By adopting the DID patented X-ring, it has achieved overwhelming wear life and longer life than genuine equivalent O-ring chains. Compensation may not be possible if the replacement work is done individually.