Check the listing for details. Union Butterfield 6541 8110608. Condition: Used. Listed at 99.00 USD. DESCRIPTIONS Union Butterfield® Pipe Tap, Straight Flute, Series: 6541 Work-Rite, Measurement System: Imperial, 1-1/2-11-1/2 Thread, NPT Thread Standard, Semi-Bottoming/Tapered Chamfer, 1-3/4 in Thread Length, 4-1/4 in Overall Length, 7 Flutes, Right Hand Cutting Direction, 1-1/2 in Shank Diameter, 1-3/4 in Tap Drill, 1-1/8 in Square, HSS, Bright, Medium Hook SPECIFICATIONS Chamfer Type : Semi-Bottoming/Tapered Cutting Direction : Right Hand Finish/Coating : Bright Hook Type : Medium Material : HSS Measurement System : Imperial Number of Flutes : 7 Overall Length : 4-1/4 in Series : 6541 Work-Rite Shank Diameter : 1-1/2 in Square Size : 1-1/8 in Tap Drill Size : 1-3/4 in Thread Length : 1-3/4 in Thread Standard : NPT Type : Straight Flute Thread Size : 1-1/2-11-1/2 FEATURES Medium hook for multi-material tappingGenerally used for pipe fittings and couplings in most ferrous and non-ferrous materialsThe nominal size of a pipe tap is that of the pipe fitting to be tapped and not the actual size of the tapNPT threads require the use of a sealant such as teflon tape or pipe compound to ensure a tight joint