Hexagonal screw in the series:
  GB code
  Standard Title
  Thread specifications
  GB/T2672-86
  Flower-shaped, 1.6-head screw
  M3-M12
  GB/T2673-86
  Flower-shaped, 1.6-head screw
  M3-M12
  GB/T2674-86
  Hexagon-shaped flowers in the first half Shen screw
  M3-M12
  GB / T 70.1-2000
  , 47.60 cylinder head screws
  M2-M64
  GB / T 70.2-2000
  Ended screw-in 47.60
  M3-M16
  GB / T 70.3-2000
  Socket head screws
  M3-M20
  GB / T 77-2000
  , 47.60-tight end set screw
  M1.6-M24
  GB / T 78-2000
  Cone, 47.60 tight end set screw
  M1.6-M24
  GB / T 79-2000
  , 47.60 cylindrical tight end set screw
  M1.6-M24
  GB / T 80-2000
  Au, 2.60 tight end set screw
  M1.6-M24