Specifications: 48T/49T single speed crankset. 165mm crank arm length. 144BCD. Mounts on square tapered bottom brackets between 113.5mm-118mm. Fits 9/16" pedals and standard 1/2"*1/8" chains. Multifunctional: sturdy and durable, precise tooth shape, smooth shifting. High-strength detachable crankset, easy to modify. The shaft is made of chrome molybdenum steel for increased crank stability. Multi-threaded fixing makes the crank more direct. Material: Aluminum alloy crank and chain ring, lightweight material, internal weight reduction design, making the crank lighter. Reduce the overall weight of the bike. Lighter and more durable than other cranks. CNC processing technology and surface anodizing treatment. Stronger, more refined and flawless. Easy to clean. 48T and 49T sizes. 49T is equipped with high-grade hollow crankset, which is necessary for racing and commuting. Package: left and right crank + disc, if you have any questions, please feel free to contact us, we will reply you in time.