3a 2nd end thread class 27 1st end thread quantity per inch w/projecting hub, 0.109 in.od by 0.080 in.lg, on thd external 2nd end unef 2nd end thread series
3a 2nd end thread class 12 1st end thread quantity per inch grumman aircraft corp, a-10 aircraft model anodize inside surface treated un 1st end thread series
3a all ends thread class 12 all ends thread quantity per inch grumman aircraft corp, a-10 aircraft model anodize surface treated un all ends thread series