【Premium Material Construction】 Our bike cassette features the top three sprockets crafted from 7075 high-strength aluminum and the rest of high-strength steel for superior durability and reduced weight, while the remaining sprockets are made of high-strength steel to ensure long-lasting performance. 【Ultra-Lightweight Design】 Weighing only 143g, this Mountain Bike Cassette is engineered to be exceptionally lightweight, helping to enhance your riding efficiency and speed. 【Wide Compatibility】 Designed for versatility, this cassette is fully compatible with XD freehub bodies and mainstream 11-speed derailleurs, making it a perfect upgrade for your mountain bike. 【Reliable After-Sales Support】 Enjoy peace of mind with our 1-year warranty and 24-hour customer service. We're here to provide prompt assistance with any questions or concerns.