Quality: This crank arm is made of aluminum alloy, lightweight and resistant to deformation. It is not easily damaged, has reliable quality, and guarantees high strength for long-lasting use.Exquisite workmanship: This bicycle crank arm adopts excellent manufacturing process with fine polishing and excellent painting , which has stable performance and stylish appearance and can add a unique look to your bike.Standard Cut: This bicycle left crank arm with standard hole precision cutout, which is easy to install and ensures a perfect fit to the bike. 170mm crank arm length without any overlap of crank arm and chainring bolt, which is a good replacement for bike repair.Excellent replacement: Size: Approx. 21 x 4 x 3cm / 8.27 x 1.57 x 1.18 inch. This 170mm bicycle crank is compatible with many bicycle models.Packaging content1 x Universal 170mm Aluminum Alloy Left Chain .