The CSMZ91X WT5 10-50T is a cassette for mountain bikes that is compatible with the XD cassette body. With 12 gears and a wide ratio, this cassette offers a smooth and efficient shifting experience. The cassette is made from high-quality materials, such as aluminum for the spider, spacer and knoskrans, and high-strength steel for the dental crowns. The finish is black and chrome, and the cassette has countersunk holes for weight reduction. With a weight of 560 grams, this cassette is an excellent choice for mountain bikers looking for reliable performance. Product specifications: - Model: CSMZ91X WT5 - Gears: 12 (wide ratio) - Function: Drive Fluid Plus - Grounds: 10-50T - Material: - spider, spacer and knoskrans: aluminum / black anodized - Tension steel tooth crowns - 42-50t tooth crowns: A7075 Aluminum - Finish: black and chrome - free holes for weight reduction: yes - Weight: 560 grams