Used on m119a1 howitzer. 2a thread class right-hand 0.660" thread length round with wrench flats head style 20 thread quantity per inch unc thread series
2a thread class right-hand 0.710" thread length flat chamfer head style 18 thread quantity per inch zinc screw surface treated flat countersunk hole in top of head 0.620 in. min 0.650 in. max depth of hole unc thread series
3a thread class right-hand 0.251" thread length oval countersunk head style 32 thread quantity per inch passivate screw surface treated unjf thread series
3a thread class right-hand 0.628" thread length flat countersunk head style 32 thread quantity per inch passivate screw surface treated unc thread series