External Metric Thread Table Chart and Fastener Sizes M1.6 - M18

What is an M8 bolt in inches? - Quora

What will be the pitch diameter for an M6 bolt? What is the method to calculate it? - Quora

Metric Thread Chart (Complete)

External Metric Thread Table Chart, PDF, Screw

For all the new MT125 owners out there

External Metric Thread Table Chart and Fastener Sizes M1.6 - M18, PDF, Screw

Metric Threads: Dimensions, Classes & Formulas (full Guide)

Fastener Thread Diameters and Installation Torques - Abbott Aerospace UK Ltd

Wrench size - Wikipedia

Manufacturing Resource, RFQ for a small bolt/stud, photo with dimensions attached.