YG-1 Extra Length Dream Drill, Series: DH421, 4.2 mm Drill Size - Metric, 0.1654 in Drill Size - Decimal Inch, 81 mm Overall Length, 8XD Cutting Depth, Spiral Flute, 43 mm Flute Length, 6 mm Shank, Straight Shank, 140 deg Point, Split Point, Right Hand Cutting, Micrograin Carbide Cutting Edge, Micrograin Carbide, TiAlN, Applicable Materials: Abrasive Plastic, Chilled Cast Iron, Cast Iron, Cast Steel, Malleable Cast Iron, Non-Ferrous Heavy Metal, Non-Ferrous Light Metal and Steel, DIN 6537 Specifications Met, Yes Through Coolant (Yes/No)