Overview of different Thread Standards Published on October 21, 2017 in The Challenges of Material Supply for AssemblyFull resolution (3796 × 1986) Overview of different Thread Standards English: Screws with different thread types. From left to right:Metric M12, 40 mm long (ISO 4017, Strength 8.8)Metric Fine M12x1.25, 40mm long (ISO 8676, Strength 8.8)Metric Fine M12x1.5, 40mm longUnited thread Standard Coarse UNC 1/2 inch, 1.5 inch long (Strength Grade 5 ( ~ 8.8 ). Dimensions in metric would be 12.7mm by 38.1mm)United thread Standard Fine UNF 1/2 inch, 1.5 inch long (Strength Grade 5 ( ~ 8.8 ). Dimensions in metric would be 12.7mm by 38.1mm)British Withworth BSW 1/2 inch, 1.5 inch long. (Dimensions in metric would be 12.7mm by 38.1mm) All screws with hex bolt heads, although they also differ slightly in size depending on the standard. This work by Christoph Roser at AllAboutLean.com is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License. Please credit the image as shown below. For digital documents and web pages please do include the links as shown below. Thank you.By Christoph Roser at AllAboutLean.com under the free CC-BY-SA 4.0 license.