Screw Thread Insert STI Tap, Thread Size 5/16 In. -18, UNC, Overall Length 2 15/16 in, High Speed Steel, Bright (Uncoated), Right Hand, Thread Length 0.834 in, Tap Chamfer Bottoming, Thread Limit H3, Class of Fit 2B-3B, Number of Flutes 4. This item has been restricted from sale in the following state (s): []