This product is suitable for retrofit folding bikes, city bikes, and electric bikes. It features high axial strength and compatibility. Standard precision machining ensures chain retention, increased service life, and reduced friction. A reliable replacement for bike repair and upgrade, compatible with various bike models. 170mm crank arm length with no overlap between crank arm and chainring bolt. Specifications: 48T double chainring, 170mm crank arm with square taper bottom bracket, includes 9/16-inch pedal axle and chain cover. Compatible with 6-speed and 7-speed drivetrains. Installation is recommended for standard bicycle applications. Color: Black. Material: Aluminum alloy. Package Contents: 1 x Crank Set. Note: Other items not included. Lighting and display differences may cause slight color variation between the image and the actual item. Measurement allowance: +/- 1-3 cm.