1set LT-03 Black Guitar Locking Nut for Electric Guitar A 6 string locking nut for electric guitar. A nut lock is used on quality guitars instead of the nut at the end of the neck. and allows the strings to be clamped at the nut. This will stop the guitar going out of tune after string bending or use of tremolo. Height adjustment of the strings at the neck end. The nut lock is 43mm wide