Graph Tech The Un-Lock nut. Designed to replace your 6 string locking nut with a standard black Tusq XL nut, providing all the stability of a double locking tremolo system with the adjustability of a traditional nut when paired with locking tuners. Pre-slotted. Available: GT6517 - Replacement for Floyd Rose Original #2 locking nut. 10" (254mm) radius. Fits up to 60 gauge Low E string. GT6518 - Replacement for Floyd Rose Original #3 and #4 locking nut. GT6519 - Replacement for Floyd Rose Special style locking nut. 12" (305mm) radius. GT6520 - Replacement for Ibanez style locking nut. 16" (406mm) radius.