One set: 12 meters.
The RS Lyon co-poly string developed and used by Robin Söderling is a high performance racket string built for control and feel.
RS Lyon was developed by Robin to fit his own game but with improved tension maintenance and a softer feel than what Robin was playing on the ATP Tour.
RS Lyon is loved by players all over the world and named "the best string I have ever played with" by tons of players.
This is a premium string highly rated by the tennis community. Watch the play test on tenniswarehouse.com and check our Youtube channel to watch the Tennis Warehouse VLOG below about this string.
https://www.youtube.com/watch?v=CAIZdtzvpVo