Round head
Flat round head
Cheese
T-head
Cup head square neck
Cup head nib
Cup oval neck
Low cheese head
GB/T 16939-2016
High strength bolts for joints of space grid structures
GJB 134.4-1986
Flat head lock bolt(ds r6)
GJB 134.5-1986
Flat head lock bolt(ds f9)
GB/T 16939-1997
High strength bolts for joints of space grid structures