ITEM: 5/1618 UNC, 2 Flute, 45° Helix, Plug Chamfer, GLT8 Finish, High Speed Steel Spiral Flute STI Tap EMUGE. MANUFACTURER: EMUGE. BRAND: Emuge. MANUFACTURER PART: BU513G10.5618. 5/1618 UNC, 2 Flute, 45° Helix, Plug Chamfer, GLT8 Finish, High Speed Steel Spiral Flute STI Tap Right Hand Flute, 3.543 OAL, 0.318 Shank Diam, 0.787 Thread Length, 3B Class of Fit, Series BU51S810CATEGORIES: Maintenance, Repair and Operational (MRO) Supplies. Taps. Screw Thread Insert (STI) Taps. Spiral Flute STI Taps. N/A. KEYWORDS: EmugeTapsScrew Thread Insert (STI) TapsSpiral Flute STI TapsN/A.