3a thread class right-hand 1.620" thread length hexagon head style 14 thread quantity per inch 0.246" min/0.248" max diameter drilled hole in threads 0.188" min/0.219" max deep unf thread series
3a thread class right-hand 0.378" thread length flat countersunk head style 0.271" grip length 28 thread quantity per inch passivate surface treated unjf thread series