Mileage is unknown, there is some visible wear on some of the teeth, zoom in on images to see the exact condition. There are some marks on the back of the cassette where the chain went behind it once, see images. Was working great on the bike it came off of. This is the CS-M9101-12 model.

Shimano XTR CS-M9101 cassette features minimal weight, maximum stiffness, and better chain retention. This cassette is built with a strategic application of aluminum, titanium, and steel materials for an optimal blend of weight savings, rigidity, and durability.
  • Compatible with Shimano Hyperglide+ chains
  • 5 titanium cogs
  • Hyperglide+ technology offers better chain engagement, stronger retention, and smoother pedaling for greater power and confidence over rapidly changing terrain
  • Micro Spline technology delivers lightweight aluminum freehub body to reduce weight and utilize a 10 tooth high gear
  • The Wide Range XTR M9101 cassette option offers 510% gear range
  • Can only be used for 1x12 set ups with the long cage rear derailleur
  • Cassette Body Type: Shimano Micro Spline
  • Drivetrain Speeds: 12
  • Cassette Cogs: 10-12-14-16-18-21-24-28-33-39-45-51
  • Weight: 367 g on postal scale
  • Range: 10-51