Authentic Makita Diamond DiscIdeal for Universal Use such as Roof Tile, Limestone, Brick, & ConcreteDiameter: 105mm or 4 inchesHole: 20mm with 16mm reduction ringSpeed: 15,300 RPMExcellent cutting speedUp to 7 mm segment height for a long lifetime, even in demanding materialsCan be used wet or dry for greater versatility