Union Butterfield Spiral Point Tap, Series: 1659AP Applix HMD, Measurement System: Metric, UNC, M8x1.25, Plug Chamfer, 3 Flutes, HSS, TiAlN Coated, Class of Fit: 6H, Right Hand Cutting, 20 mm Thread Length, 90 mm Overall Length, 0.318 in Shank Dia, D5 Thread LimitDesigned for through hole tapping materials with a hardness of >38 RcPremium substrate provides superior abrasion resistance and edge strengthTiAlN top coating lowers the coefficient of friction, improves thread quality, affords higher operating speeds and longer tool life