Replace Your Stock Timing Chain With A PRW Dual Chain Set, These Double Roller Timing Chains Are Extremely Durable Compared To Your Stock Components, PRW Machined Steel Alloy Gears Add Longevity And Will Not Fail Prematurely Or Stretch Like Most Single Roller Timing Chains, Comes With A 9 Keyway Crank Gear For 2 Degree Adjustments Increments, Made in the USA.