- Precision Thread Size Check Keychain: This compact bolt size finder keychain allows for quick and accurate thread size measurement, ensuring you have the right size on hand whenever you need it. - Clear Dual Unit Marking: The keychain features a dual measurement capability for both Metric (8-25 mm) and SAE (5/16-1") bolt sizes. With an adjustable opening, you can easily customize the measuring range, and the clearly marked scale ensures easy readability. - Durable Construction: Crafted from stainless steel and aluminum alloy, this keychain gauge tool boasts a polished, smooth surface for longevity. Its durable design allows for frequent use, while the attached keychain ensures it is conveniently accessible at all times. - Versatile Applications: Perfect for measuring threads on various nuts, bolts, and screws, this tool is essential for DIY enthusiasts, mechanics, and professionals alike. Whether you're working on home repairs, automotive projects, or construction tasks, this size finder delivers fast and precise measurements to enhance your workflow. - Always Within Reach: The keychain design means you can easily carry this tool on your belt or in your bag, making it an indispensable companion for any project.