Product Type: This is a wind instrument repair tool, specifically designed for the maintenance of saxophones and flutes. It's an essential tool for musicians and instrument repair professionals Measurement Range: The tool features two sets of measurements, ranging from (2,4,6,8,10,12) mm and (3,5,7,9,11) mm respectively. This wide range allows you to accurately measure the opening height of your wind instruments Material: Made from steel material that ensures longevity and reliability in use. It's designed to withstand regular use without losing its precision Compact Size: This tool is compact and lightweight making it easy to carry around in your instrument case or toolkit Package Contents: Each package contains piece of this measurement tool for wind instruments Specification: Material: Steel Size Chart: 6cmx1.3cmx0.3cm/2.36inchx0.51inchx0.12inch Package Includes: 1Flute Clarinet Opening Height Gauge Note: Please allow slightly errors 1-2cm/0.39-0.79inch differences due to manual measurement.