The box only says Marazzi K17S, I don't have a more precise designation. The size is 15x90cm.
The grout color should definitely not be like that in the rest of the house, but unfortunately I don't know much about it and therefore find it hard to imagine which grout color I should choose for a parquet effect. Brown or beige perhaps?
Under the heater we will leave it as it is, it will be installed today and is so large that you can hardly see the grout anyway. I have already contacted the tiler to make sure a different color is used in the rest of the house, but I am still uncertain which one.