How is the camlock coupling size calculated?
This is an inch size
Commonly used inch
1 inch is equal to 25.4 mm
1/4 “means that 1/4 inch equals 0.25 * 25.4 equals 6.35 mm
If it is thread, then there should be a number of teeth, such as the number of 1/4 “-24UNF
Meaning a large diameter of 6.35 in 1 inch 25.4 mm with 24 screws