If you shred aluminum sprockets, Dirt Tricks has the solution! What makes their rear sprocket so superior to anything sold? One-year warranty. Heat-treated nickel / chrome plated and laser-etched. Machined to the tightest industry standards and tolerance. Unique "minimalist" design and appearance. Chrome-moly steel - 2.5x stronger than stainless steel. Three times stronger than 7075 aluminum. Weighs around 18 ounces (48-tooth).