Slot
Countersunk head
Raised countersunk head
Countersunk head square neck
Countersunk head with nib
Square countersunk head
Countersunk Cheese head
T-head countersunk
Reduced shank
Normal shank
Full thread
Semitubular end
BS 325-4-1947
Black 80° countersunk nibbed bolts and countersunk round bolts-Table 4