3b thread class left-hand 1.2810" overall length 0.1895" bore diameter 32 thread quantity per inch chromium inner member surface treated ball type unf thread series
3a thread class right-hand 2.4380" overall length 0.3745" bore diameter 24 thread quantity per inch chromium inner member surface treated ball type unf thread series
3a thread class right-hand 2.7500" overall length 0.2495" bore diameter 24 thread quantity per inch magnetic particle inspected /magnafluxed/ chromium inner member surface treated ball type unf thread series