These strings are made of 100% polyamide multifilament. This ensures that you have a lot more power and more comfort while playing tennis. This ensures that you are less likely to get injured. Thanks to the PU 400 Inside technology, your stringing is 400% more elastic. This will also increase the playing comfort and dynamics. The anti-abrasion coating prevents abrasion and ensures a good durability of the strings and the racket. All in all, these are strings that deliver lots of power and comfort.