The quality of the string button has a great impact on the pitch. It is difficult to adjust the string button that is not good enough to be just right. It is a little higher and a little lower. If you go too far, you want to turn back, but you find it idling again. The inferior string button is even worse. It is either loose when touched, or loose and tight when turned. Even if some strings are not installed, they will rotate very tightly or can't rotate. The new strings break when they are installed without adjusting a few times. The good string button, even when using the tuning clip, rotates very smoothly and the pitch is very accurate. A good set of guitar string buttons can greatly improve the performance of the guitar.