Ceramic tiles Tau Serenastone Graphite mat rec Tile material: porcelain Tile style: natural stone Surface: micro textured Finish: matt Glazed: yes Frost resistant: yes Rectified/calibrated: yes Slip resistance: R9   Porcelain tiles are suitable for use as both wall tiles and floor tiles. Porcelain tiles are frost-resistant and suitable for outdoor use. In outdoor conditions where there is a risk of slipping, we recommend using tiles with R11 slip resistance. The tiles have rectified edges that allow them to be installed with a minimum joint width. The result is a more even wall or floor.