Cross recess
Hex socket
Hex chamfered single face
Flat round head
Cheese
Square
T-head
Triangle
Y-shape
Hex chamfered double faces
Cheese with shoulder
Octagonal
Nylon Insert
Straight-knurl
Shoulder
Blank shank
Tubular end
Semitubular end
MS 21077H-1997
Self-locking nuts,two lug
MS 21077H-1999