The MK Diamond 159406PK20 MK-99SWD is a 20-pack of 4-1/2 Inch Segmented Rim Wet/Dry Blades, 7/8-Inch to 5/8-Inch Arbor. The 159406 blades easily cut brick, block, landscape pavers, fiber cement board, concrete, stucco, roof tile, asphalt and most masonry materials. These blades can cut 70 times longer than abrasive blades.