Size: L:30 H:0.5 W:30 (cm) (cm) 100% Indian Cotton.  Gentle for skin and extremely durable. The high durability of these towels combined using 100% Indian cotton will ensure the towels wont become thin. With a density of 500 gsm and available in a contemporary white colour these 30x30 cm face towels are super absorbent. What is GSM? GSM stands for Grams per Square Meter and is essentially the weight/density of the towel. A higher GSM rating of around 500 to 600gsm indicates a more thicker, dense towel which will be more durable and longer lasting than a towel with a lower GSM rating. It's usually tempting for institutions to consider getting cheaper, alternative towels with a lower GSM rating but it's not cost effective to do so in the long run.