• Best For: Crews that need a 4-1/2 inch core hole through material with moderate to high steel reinforcement and want the MK Diamond 156390 size rather than another diameter in the MK Black Supreme line.
• Highlight: MK Black is a supreme grade MK Diamond core bit engineered for exceptional footage and fast, aggressive drilling, and part 156390 delivers that in a 4-1/2 inch diameter.
• Expert Note: This MK Diamond bit is a wet core bit, and its 4-1/2 inch diameter sets the finished hole size, so confirm that diameter before ordering because 156390 is sold separately from the other MK Black Supreme sizes.
