Guyker String Headless Guitar Bridge String Lock Nut Style:7 String as shown by the product

as shown by the product title and images

Overall the knob is 20mm in diameter and 24

8mm max string gauge support

Block size：

Take off the pickguards and loosen the screws that secure the humbuckers or pickups

Guyker String Headless Guitar Bridge String Lock Nut Style:7 String as shown by the productSpecifications: String Lock Options: Available for 6 string, 7 string basses and 8 string basses. Dimensions (6 String): Length: 42mm Width: 20mm Height: 9mm String Spacing6. 6 7. 5mm Dimensions (7 String): Length: 48mm Width: 20mm Height: 9mm String Spacing6. 6mm Dimensions (8 String): Length: 54mm Width: 20mm Height: 9mm String Spacing6. 1 7mm Size Picture