Practical bike chain checker help you judge whether the chain needs to be replaced by the chain wear stretch ratio, ensure the safety of riding. Features: Chain checker can help you judge whether the chain needs to be replaced by the chain wear stretch ratio. All aluminum alloy material, has nice durability, corrosion and oxidation resistant, with high hardness. Readings are laser-engraved technology, accuracy and clear, easy to view, not easy to wear. Small and lightweight, easy to carry and store. Suspension hole design, support suspend, save space. Easy to operate and use, compatible with most bicycle chains, perfect for mountain bike or road bike. Specifications: Color: Black/ Red/ Orange/ Blue/ Green/ Purple(optional) Material: Aluminum Alloy Item Size: 128 * 10 * 10mm/ 5.0 * 0.4 * 0.4in Item Weight: 35.6g/ 1.3oz Package Size: 190 * 30 * 30mm/ 7.5 * 1.2 * 1.2in Package Weight: 52g/ 1.8oz Packing List: 1 * Chain Checker