Guitar Hardware-ROLLER NUT-Help Stay In Tune-Gold Brand New Notice how easy your guitar can go out of tune when you use a standard nut? Its caused mainly by friction. With the roller nut, the strings sit on the little "wheels" allowing them to return to the spot they were before you went nuts with the whammy bar, and helps keep you in tune without the hassle of a locking nut. Fender & Wilkinson both designed a similar nut, and this one is based off of the same concept. It is brand new and in perfect mint condition. If you have any questions, please feel free to contact us. Please note: This item requires modification to the guitar neck. Installation requirements may vary from instrument to instrument.