The MotoSport.com Driven Racing 520 Steel Sprocket And Chain Kit includes ONE Driven Racing Front Sprocket, ONE Driven Racing Rear Sprocket, and your choice of ONE Premium Drive Chain, each with the following features: Sprockets / Chainwheels Included: Every Driven Sprocket is manufactured to a rigorous standard of quality which is unsurpassed in the industry. Driven Racing Front Sprocket: Designed using Driven Racing's proprietary EST Technology. Driven steel sprockets are manufactured using only the highest quality 45C steel available. Steel sprockets are heat treated and then quenched for maximum strength and durability. Every sprocket is guaranteed against defects in materials and workmanship; performance and reliability in one sprocket. Lowered surface to remove unnecessary weight. All Driven front sprockets are drilled to reduce overall weight.