Feature: 1. Made of high quality aluminum alloy, it is light weight, high strength, strong resistance to deformation, and durable. 2. Standard holes are precisely cut to ensure a perfect fit to the bicycle and easy to install. 3. There is only one crank arm on the left. The length of the crank arm is 170mm 6.7in. There is no overlap between the crank arm and the chainring bolt. 4. The bicycle crank arm helps ensure maximum chain retention, prolongs service life, and reduces friction and noise. 5. A good replacement for bicycle repair, compatible with many bicycle models, and has a wide range of use. Specification: Item Type: Bike Crank Arm Material: Aluminium Alloy Product Color: As Pictures Shown Total Length: Approx. 205mm 8.1in Two Holes Center Distance: Approx. 170mm 6.7in Product Weight: Approx. 210 271g 7.4 9.6oz Specification: 170mm crank on the left side of the chainring. Package List: 1 x Bike Crank Arm Note: 1. It is suitable for the square hole bottom bracket, please pay attention to whether the crank of the original car is a square hole or a diamond hole when purchasing(please refer to the product picture). Keep the left and right arm holes the same. Some exercise bikes may not be available, please confirm the length and connection port.2. If the crank has been replaced once, the bottom bracket needs to be replaced when the crank is updated again, because the life of the bottom bracket is generally only 2 times.3.