Style 1 - Hexagonal

Style 2 - Round Hex One End

Style 3 - Round Spanner

Style 4 - Round Tapped Both Ends

Style 5 - Round w/ Ext Threads

Style 6 - Round w/ Notch for Keeper

Style 7 - Round w/ Flats for Drop-In

Style 8 - Round w/ Cotter Pin Holes