AMERICAN OR EUROPEAN STANDARD TO MEASURE THE TOOL?

We use the American standard to measure the tools, that is by the diameter of the steel. The European standard measures across the flute. In a world where we use both it does get confusing at times. Here’s a simple chart to show both. American —– European 3/8 ————– ¼ ½ ————— 3/8 5/8 ————– ½ ¾ ————— 5/8 7/8 ————– ¾ 1 —————–7/8