• Highlight: MK Diamond's MK Orange Premium grade core bit blends fast drilling with rebar tolerance — its high diamond concentration cuts faster than the standard MK Yellow line on lightly reinforced concrete.
• Best For: Plumbing and HVAC contractors drilling 4-1/4" penetrations for drain lines, vent stacks, and conduit through reinforced concrete walls and slabs.
• Expert Note: The 4-1/4" (108mm) MK Orange Premium bit handles light-to-moderate steel reinforcement; pair with a stand-mounted water-fed core drill at ~600-900 RPM for clean cores through 6-8" structural slabs.
