What Our Gearhead(R) Experts Are Saying: "I've been riding the 10-51T XT cassette for the last season and it's easily the smoothest-shifting drivetrain I've used. Even on steep climbs under power, the shifts are crisp, and the 510% range has saved me more than once when I've been deep into a big day. It's bombproof, too-I haven't even touched it with a brush."From lung-busting climbs to fast descents, the Shimano DEORE XT 10-51T Cassette gives us the range and responsiveness we need on big days in the saddle. Redesigned with Shimano's evolved HYPERGLIDE technology, this cassette improves shift timing and consistency under load-whether we're climbing in the granny gear or dropping gears mid-sprint. The CS-M8200 combines steel and alloy cogs to balance weight savings with the long-wearing durability Shimano is known for. With a 10-51T range offering a massive 510% of gear spread, it's the most versatile cassette in the DEORE XT lineup. It mounts to a Micro Spline freehub and pairs perfectly with 1x12-speed drivetrains for everything from XC racing to alpine epics.