Product Description Marshalltown RB192 Masonry Rubbing Brick 6 X 3 X 1 20 Grit From the Manufacturer This rub brick is crafted with a fluted silicon carbide surface and Pro-Grip handle-making it the preferred brand for many tradesmen. The comfortable, well-contoured handle minimizes fatigue. This rub brick is the fastest, most economical cutting medium known for dressing down all kinds of concrete work.