Hey mountain bikers! This BOLANY crankset is seriously awesome for upgrading your ride. It's a hollow integrated design that's way lighter than those old square tapered cranksets - we're talking about 1000g total weight, which is pretty impressive. You get 170mm crank arms with 104BCD and your choice of either 22/36T or 24/38T chainring combinations. The materials are top-notch too - 7075 T6 aluminum alloy for the crank arms, steel chainrings that are super durable, and a chrome molybdenum steel shaft that really improves stability. The chainrings have this precision tooth shape that makes shifting super smooth, and they're removable so you can easily swap them out later if you want. It comes with a BB91 threaded bottom bracket that fits 68-73mm bottom bracket shells on most MTB and road bikes. The built-in bearings have high lubricity for smooth pedaling and noise reduction - seriously, no more annoying creaking sounds like you get with some cranksets after a while. They use CNC machining and surface heat treatment in the manufacturing process, which means higher strength and a more polished look. The internal weight reduction design makes it lighter without sacrificing durability, and the multiple thread fixation makes the crank force more direct. This thing is compatible with 10-speed and 11-speed systems, and it even includes aluminum alloy gaskets and a crank dust cover to protect everything. If you're looking to upgrade your bike's drivetrain with something reliable, lightweight, and quiet, this BOLANY crankset is definitely worth checking out!