Description: With help of the bicycle chain tensioner, it can be used to adjust the chain tightness of folding bicycles. It is a perfect replacement for your old or damage one, easy to install and replace. As a great accessory for folding bicycles, our bicycle chain tensioner has many kinds of advantages, like high durability, rust-proof, corrosion resistance, heat-resistant, sturdy and so on. You can use it for a long time. It is constructed of metal material. The length of the screw (thread part) is about 2.8cm, and the aperture is 1cm. This product is perfectly suitable for bike, road bike, MTB and so on. Item Name: Bike Chain Adjuster Material: Metal Features: Rustproof, Corrosion Resistant, High Hardness Size Details: Length (Thread Part): 2.8cm/1.1" (Approx.) Aperture: 1cm/0.39" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 5 x Bike Chain Adjuster