... 2. size: m6-30x20-250mm 3. certificate:ISO9001 4.material :Carbon Steel,swrch35k carbon steel hex boltcarbon ... ANSI, ISO, GB3)size:m6-m30,1/4''-1''4)length:10mm-250mm,1/2''--10''Detailed size descriptionA ... 250 M27*90-270 M30*90-3005)grade:4.6,4.8 ,5.6,5.8,6.8, ... and marketing hex bolts. We have domestic advanced automatic cold heading machinery and equipment, strong technical forces,comprehensive ...