The AGS Brake Line Fitting Gauges come in both SAE/Inch and ISO/Metric versions. The Brake Line Fitting Gauge is an accurate and easy-to-use thread checker for the most common thread sizes found in automotive braking systems. Conveniently assembled onto a wire loop, it is especially well suited for distinguishing between similar inch and metric threads. This tool is a great addition for Auto, Motorcycle, Marine, ATV or RV Repair Shops. Features – Each size has a male and female end checker on the same gauge. – Thread sizes are permanently stamped onto each gauge. – Inch gauges are clear zinc plated, metric gauges are black oxide. – A wire cable with plastic coated loop at each end provides convenient hanging in many locations. – Each gauge rotates freely on the wire cable for quick and easy thread verification.