Check the listing for details. OSG 2807401 Spiral Point Tap,#6-32,HSS-E 2PHV7. Condition: New. Listed at 22.37 USD. Spiral Point Tap, Thread Size #6-32, UNC, Overall Length 2 in, HSS-E, Black Oxide, Right Hand, Thread Length 5/16 in, 75 Percent Thread Drill Size #36, Thread Limit H2, Class of Fit H3, Number of Flutes 2 These taps have a unified thread standard. UN coarse (UNC) taps have fewer threads per inch than UN fine (UNF) taps. Compared to UNF taps, UNC taps perform better in threading applications on brittle materials and are less likely to cross thread. Coarse threads can also withstand more physical abuse than fine threads. UNF taps have more threads per inch than UNC taps. Compared to UNC taps, UNF taps perform better in threading applications on thin-walled workpieces and hard materials. Fine threads provide more tensile strength and shear strength than coarse threads. The black-oxide finish.