Royal Oak String Cleaner is designed to remove the sticky build-up on strings. Royal Oak is a quality product made by Larsen which is solvent free and bio-degradable.
In order to get the very best sound and response quality from the strings any build up of rosin should be removed. During breaks in playing, it is recommended that you wipe off any remaining rosin from the strings with a soft cloth. After playing on a weekly basis at least, ensure you clean the string with the string cleaner.