Features: Premium zincs alloys guitar locking nut ensures durability performances and precise string stability for double locking tremolo systems, available in black/gold/silver finishes with 42mm/43mm size options. Engineered with high strength zincs alloys construction and double size compatibility (42mm/43mm), this locking nut securely anchors guitar strings while offering color customization to collocation instrument aesthetics. Ideal for electric guitarists seeking reliability tuning stability during aggressive tremolo use, particularly players of Rose styles or similar double locking bridge systems. Perfect for live performances, studio recordings, or practice where consistent tuning and reduced string slippage are critical for optimal musical expression. Quick install guitar hardware accessory enhances playability without speciality tool, serving as an essential upgrade for both professional musicians and hobbyists maintaining stringed instruments. Specifications: Color:Six Choices Dimension:4.2x1.6x0.9cm/1.65×0.63×0.35in 1.67×0.84×4.3cm/0.66×0.33×1.69in Component:zincs alloys Package Includes: 1set guitar lock note: 1.Please allow 1-2cm errors due to manual measurement, making sure that you will not mind before order. 2.Due to the differences between different monitors, the picture may not reflect the actual color.