The SHIMANO ULTEGRA R8100 Series 11-30T 12-speed HYPERGLIDE+ Road Cassette Sprocket is a high-quality cassette designed specifically for road bikes and racing bikes. Made by Shimano, a reputable brand in the cycling industry, this cassette features a 30-tooth largest sprocket and an 11-tooth smallest sprocket, providing a wide gear range for optimal performance. With a weight of 291g and compatibility with Shimano components, this cassette is a reliable and durable choice for avid cyclists looking to enhance their biking experience.