PLAY AGGRESSIVE, SHRED OR BEND STRINGS WITHOUT WORRY! One of the key causes of tuning frustration is string binding at the nut. Black TUSQ XL Nuts are impregnated with PTFE, the slipperiest substance on earth, which alleviates the binding grip. Guitar strings simply glide back into tune! With these GraphTech Nuts you will hear more richness from every note you play. Engineered from the same material as our highly esteemed TUSQ, it has all the tonal benefits, bringing out the hidden harmonics by transferring your strings vibrations efficiently to the guitar. Black TUSQ XL is consistent from piece to piece, and within each piece, to offer harmonically rich tones without the problems associated with natural materials. Yuki Ozawa, Ibanez - "We use Black TUSQ XL on all our high end Prestige & Premium Ibanez guitars and basses. We selected Black TUSQ XL because of its superior tone and tuning stability." You can view the full range of GraphTech brands and products HERE