flush (flat) countersunk (included angle - less than 135 deg w or w/o chamfer) head style 0.376" grip length ns" letters after the material code "b" indicate no preference to lock type (may be visible or internal) . rivets with no letter code (indicating visible lock type) chromate sleeve surface treated
3a thread class right-hand 0.580" thread length flat chamfer head style 32 thread quantity per inch color black oxide fastener surface treated unf thread series
3a thread class right-hand 0.657" thread length double hexagon w/hole head style 24 thread quantity per inch passivate surface treated unjf thread series
3a thread class right-hand 0.313" thread length flat countersunk head style 0.178" grip length 32 thread quantity per inch aluminum surface treated unjf thread series
3a thread class right-hand 0.386" thread length flat countersunk head style 0.865" grip length 28 thread quantity per inch navy special project cadmium or cadmium surface treated unjf thread series
3a thread class right-hand 0.444" thread length flat countersunk head style 0.865" grip length 28 thread quantity per inch passivate surface treated unjf thread series
3a thread class right-hand 0.505" thread length flat countersunk undercut head style 0.865" grip length 24 thread quantity per inch furnish with one o ring unjf thread series
3a thread class right-hand 0.400" thread length dished hexagon head style 1.740" grip length 28 thread quantity per inch cadmium surface treated unjf thread series
2a thread class right-hand 0.230" thread length hexagon head style 40 thread quantity per inch navy special project countersink internal hole 90 degrees by 0.190 in. dia passivate surface treated concentric hole unthreaded unc thread series
