High-strength alloy main body, hard and compressive, H-shaped chain groove structure, avoid chain skipping when changing speed, small size design, easy to carry, magnetic absorption design, easy to store. Using aluminum alloy sliding rod design, it can slide smoothly left and right. H-shaped chain groove design does not jump chain H-shaped chain groove structure avoids chain skipping during shifting Magnetic storage design. The flywheel inlaid magnet can be adsorbed on the iron tool wall, and there is a buckle placement slot, which can absorb a pair of buckles for backup Exquisite, compact and convenient. Small size design, easy to carry when going out, can be put in trouser pockets, tail bags, backpacks, can fix the chain, avoid the chain slack, just scratch the paint during transportation. Product name: Chain tensioner Type: Standard version Colour: black + blue Material: aluminum alloy Package Contents: 1 * Chain tensioner 2 * Sponge ring Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.