Terramar Bone is a 24" x 24" porcelain tile with rectified edges, which allows a tighter grout joint. The face carries the movement of quarried stone. A PEI 4 rating suits heavy residential and light commercial floors. It carries an R9 slip rating, normal for a dry interior floor. It is frost resistant, so it can run from an interior floor onto a covered porch or patio. A box holds 3 pieces and covers 11.51 square feet. Made in Spain.