"Size","Pitch (coarse)","Fine pitch","Across flats — ISO","Across flats — DIN","Head height k"
"M3","0.5","—","5.5","5.5","2"
"M4","0.7","—","7","7","2.8"
"M5","0.8","—","8","8","3.5"
"M6","1","—","10","10","4"
"M8","1.25","1","13","13","5.3"
"M10","1.5","1.25 / 1","16","17","6.4"
"M12","1.75","1.5 / 1.25","18","19","7.5"
"M14","2","1.5","21","22","8.8"
"M16","2","1.5","24","24","10"
"M18","2.5","1.5","27","27","11.5"
"M20","2.5","1.5","30","30","12.5"
"M22","2.5","1.5","34","32","14"
"M24","3","2","36","36","15"
"Reference only — confirm against drawing. ISO 4014 / ISO 4017 · DIN 931 / DIN 933. REL India"