Genuine EVH D-Tuna for Floyd Rose Bridges - Gold Fender Part #555-0121-469
The EVH D-Tuna is a unique patented device that enables players to drop the E to D and back, in an instant. D-Tuna has been standard equipment on Eddie Van Halen's personal guitars as well as signature series locking tremolo-equipped guitars since the early 90's. Since then thousands of D-Tuna's have been sold all over the world. D-Tuna is proud to be endorsed by many professional players such as Warren DeMartini (RATT), Michael Wilton (Queensryche) and Dave "The Snake" Sabo (Skid Row) just to name a few. Bottom line...It's simple to use and it works.

"It couldn't be easier to install. You remove the string locking screw from the low E-saddle on the bridge and replace it with one of the two D-Tuna locking screws, the spring assembly and the D-Tuna. And that's just about all there is to it." - Edward Van Halen