How to Read a Metric Screw Thread Callout

http://www.mrmetric.com/?leadsource=M... Whether you're a part-time hobbyist or a seasoned mechanic, there will be a time when you have an unidentified hole, bolt, or screw. You will need to know exact size. Screw thread callouts are a standardized system for determining the size, thread pitch and length. To read a screw thread callout, you need to learn the guidelines.

The ability to read screw thread callouts will allow you to quickly find the correct screw sizes. If your fastening application calls for standard or non-standard metric fasteners, or if you just have a question about the markings on your fasteners or assembly, call us at 1-866-501-9504 and Mr. Metric staff is happy to help!