Used on U2. 3a thread class right-hand 0.469" thread length dished hexagon head style 1.615" grip length 24 thread quantity per inch unjf thread series
Used on cn-235 transport aircraft. 3a thread class right-hand 0.316" thread length pan head style 0.428" grip length 28 thread quantity per inch cadmium surface treated unjf thread series
3a thread class right-hand 0.625" thread length flat countersunk head style 0.125" grip length 32 thread quantity per inch two grooves 180 degrees apart full length of fastener passivate surface treated unc thread series
Used on nsn: 2420-01-532-3399. hexagon head style hex head bolt metric course series thread to head per iso 4017; material class 8.8 per iso 898/1; finish zinc dichromate zinc surface treated