Shimano's lightweight and modern looking SM-CRE80 chainring features Shimano Dynamic Chain Engagement+ for smoother pedaling and better chain retention over bumpy terrain. Dynamic Chain Engagement (DCE) is used to hold the chain and help prevent chain jump out. This is achieved by using a broader and taller tooth profile in conjunction with a special hooked leading edge and alternate profiled tooth shaping. This provides superior chain retention, lower driving sound, increased durability and drag to a minimum.