Gears are machined from hardened steel alloy with an aluminum, gold anodized center section for adjustability, fully compatible with the stock Polaris timing chain. The BC adjustable cam gears for the Polaris Pro R platform are the perfect way to gain top end or low end torque depending on how you dial in the gear settings. These gears allow for 5 degrees of advance or retard for both intake and exhaust cams with easy to read indicator marks. Includes 4 ARP stainless steel bolts per gear for added clamping security. Fits all Polaris Pro R and Slingshot models. Pair of intake and exhaust gears.