More and more Metric specifications are showing up on manufacturing prints in the USA. To help clarify abbreviations we offer explanations below:
American Society of Mechanical Engineering / United States Cutting Tool Institute, all standards are specified in the Imperial measurement (Inches).
Deutsches Institut Fur Normung / German Institute for Standard, all measurements are to the Metric system.
Japanese Industrial Standard, all measurements are to the metric system
International Standardization Organization, all measurements are to the metric system.
Other countries have their own standards that would relate to specific industries like aircraft and automotive applications. By way of example, in the USA other standards like NAS – National Aero Space. SAE – Society of Automotive Engineers are related to specific of industries.
Here are some examples of differences in Metric Jobber Drills versus an Inch