absoluteBLACK Premium Oval 145/112 BCD Road Chainrings utilize absoluteBLACK's top-tier design features to greatly improve traction and speed. They are designed for Campagnolo Super Record Record and Chorus 4-bolt cranks. Optimized with smooth shifting in mind premium chainrings have a patented shifting ramp design. Chainrings are crafted from CNC machined 7075 aluminum and feature an anodized finish for exceptional durability.Oval shape reduces stress on knees helps to keep your legs fresh and does not feel any different while ridingChainring design reduces the possibility of leg cramps and allows you to maintain a better cadence while climbing11 and 12-speed compatibleUse original bolts for installation