3a all ends thread class 18 all ends thread quantity per inch used on C17a acft phosphate body surface treated male coupling half unjf all ends thread series
Used on slave filter assembly,lube oil. 2a 1st end thread class 12 1st end thread quantity per inch hydrostatic pressure test 280 psig at 64 deg-72 deg f; holed drilled between first enamel surface treated un 3rd end thread series