Expanded line of SMD Replaceable Head Drill includes 12XD drills. SMD Replaceable Head Drills allow for deep hole making at a lower cost - SMD users buy just one drill body to fit up to five head sizes. Featuring an original radial serration coupling design, SMD drill heads, or tips, are designed for high precision stable drilling. A polished flute ensures good chip evacuation. The SMD nickel-plated body provides longer tool life than conventional replaceable tip drill bodies. A tough carbide substrate with patented DEX coating offers excellent wear-resistance at the cutting edge. A rigid serration coupling system affixes the replaceable carbide tips to the drill face, improving drill accuracy and repeatability.