Size 50T The Dirt Tricks Rear Sprocket was designed and patented by Dirt Tricks president and engineer Greg Burns in 2002, using his knowledge of aerospace steels, heat treatments, as well as FEA stress analysis. Being an expert desert racer, Greg became tired of changing aluminum sprockets every two months. His goal was to create a sprocket that would last an entire season of hard riding, yet be comparable in weight to aluminum. Thus, the Dirt Tricks sprocket was born. It required two years of development and testing, but the end result has proven to be the toughest, most durable off-road sprocket available. Our Chrome Rear Sprockets are 2.5 times stronger than stainless steel and use a unique “minimalist” design and appearance. We back these sprockets with a one year guarantee: if you wear it out, we will replace it. Our Black and Chromatic Rear Sprockets use our latest design and are a revolutionary change in weight and color. Our new Dirt Tricks Zirconium Rear Sprockets are 2oz lighter than our chrome plated design, and are comparable to most of the performance aluminum sprockets and lighter than the twin metal designs available. The new coating on these sprockets reduces friction up to 50%, increases durability, and looks sharp! Our Special Edition sprockets will outlast any sprocket on the market, and we back that up with our 2 year guarantee. Proudly made in the USA.