Savarez Accordion Accessory (500CJ) Cristal Corum Series^High tension^Cristal clear nylon trebles, Corum silver plated wound basses And CORUM wound basses The set CORUM PR is made of: rectified nylon trebles (with NEW CRISTAL quality) And CORUM wound basses The set CORUM PR is made of: rectified nylon trebles (with NEW CRISTAL quality)