This part specifies the hexagon socket head countersunk head self-tapping screws with thread specifications ST2.9~ST6.3. If other technical requirements are required, they should be selected from current standards (such as GB/T 5280, GB/T 3098.5 and GB/T 3103.1).
GB/T 2670.3-2004 history
2017GB/T 2670.3-2017 Hexalobular socket raised countersunk (oval) head tapping screws