This towel’s GSM rating is 420 GSM. GSM stands for grams per square metre and indicates the weight and density of the towel. M&S' towels range from 450-800 GSM. At the lower end of the scale, 450-600 GSM signifies a lightweight towel: good value and quick-drying, with added benefits such as low-twist yarn to make them feel more like their heavier-weight counterparts.  At the higher end of the scale, 600-800 GSM signifies a heavier, more luxurious towel. The pile in these deluxe towels is denser and more lavish. Towels at the lower end of this range are great for everyday use, while those at the higher end resemble the towels you’d find in a luxury hotel. This soft and absorbent bath towel features a dramatic print of the Solar System. The towel is made from pure ethically sourced cotton. A matching bedset is available in the same design.