The MK Diamond MK-50S is a 20-inch segmented diamond blade built for the walk-behind and high-speed saws that concrete and masonry crews run on jobsites every day. It arrives with a .142-inch segment width and a 1-inch arbor, the standard mounting for larger flat saws, so it drops onto the machine without bushings or adapters on most setups. Contractors reach for a 20-inch blade when the cut has to go deep in one pass, and the segmented rim is what makes that possible: the gullets between segments carry slurry and spoil out of the kerf so the diamond keeps biting instead of glazing over. If you are cutting control joints, trenching for conduit, or opening a section of slab for a repair, this is the size class that does it without a second pass.
Built for
Control and expansion joints in fresh slabs
Segmented blades clear their own slurry, which is what lets a crew walk a straight joint at a consistent depth without the blade loading up and stalling. A 20-inch diameter gives the depth headroom to cut joints in thicker pours in a single pass.
Utility trenching and slab openings
When conduit, plumbing or a floor drain has to go through an existing slab, a large-diameter segmented blade lets you score both sides of the trench cleanly so the interior breaks out with a hammer instead of a full demolition.
Masonry and block work on larger saws
The MK-50 family is aimed at concrete and block. Mounted on a high-speed saw it handles the straight cuts that a brick saw is too small for, which is the usual reason a crew steps up to the 20-inch size.
Repair and demolition cut-outs
Cutting a clean perimeter before breakout reduces the amount of patching that has to happen afterward, which is where a lot of the labor cost on a slab repair actually sits.
Specifications
- Manufacturer: MK Diamond Products
- Series: MK-50S
- Blade diameter: 20 inches
- Segment width: .142 inch
- Arbor: 1 inch
- Rim style: Segmented
- Part number: 128736
Frequently asked questions
What arbor size does the MK-50S 20-inch blade use?
It uses a 1-inch arbor, which is the common mounting size on larger walk-behind and high-speed concrete saws. Check the shaft on your saw before ordering, because smaller handheld saws typically use a 20mm or 5/8-inch arbor and would need a different blade.
What does the .142-inch measurement refer to?
That is the segment width, sometimes called the blade thickness at the cutting edge. It sets how wide the kerf will be. A wider segment removes more material and generally holds up longer under load, but it also asks more horsepower from the saw.
Why choose a segmented blade instead of a continuous rim?
Segmented blades have gullets between the diamond segments that pull slurry and debris out of the cut. That keeps the diamond exposed and the blade cutting on concrete and masonry. Continuous rim blades are the opposite trade-off and are used for chip-free cuts in tile and stone.
How do I get longer life out of a diamond blade?
Keep the blade cutting rather than riding, let the saw do the feeding instead of forcing it, and make sure the machine is delivering the water or airflow the blade is rated for. Most premature blade wear traces back to a dull-run or an underpowered saw rather than the blade itself.
Discount Cleaning Products is an authorized dealer and stocks this part alongside the matching filters, bags, belts and accessories for the same machine, so a single order covers a full service visit. Orders are handled by a US-based team that works with these machines every day, and part-number questions are answered by people who can cross-check the fitment before you buy.
