These saddles came stock on lower priced and imported guitars that had the "Traditional" fulcrum tremolo systems installed on them. Sporting brass rollers, they are a 4 way saddle that have a full and inviting warmth. If you desire a different tone, you can use the Teflon rollers for mix cutting solos or the 80's tone Steel rollers for those of you who still prefer wearing black T-shirts. Did you see the unplugged tone comparison video? The saddle locking screw is not included. FYI: You can also replace the black roller 2500 Pro saddles with these Standard saddles because the Pro saddles are no longer available and are discontinued. In fact all Fulcrum parts are discontinued. Once gone, they are gone forever.