I have being playing Strats for years. These springs only come with the Made In American Strats. I don?t understand why Fender don?t include them with the Made In Mexico guitars as well. The extra cost is minimal and they transform the way a ?screw in? Tremolo Arm plays. All the irritating wobble disappears without having to screw in the arm so tight that you either cannot move it or you risk stripping the threads.
I have used them on Mexican, Squier and virtually every copy I have come across. If the guitar has a Fender style bridge with a screw in tremolo arm, both six point and two point styles, these springs will work. Just unscrew the tremolo arm, drop in the spring and screw the tremolo arm back in, until you just start to feel resistance. Try not to over tighten as this will reduce the life of the spring. With use and I mean a lot of use, the springs can start to compress. When this happens, just screw in the tremolo arm one turn and off you go again. After about three tightens, which for me is after at least three years heavy use, it is time to replace the spring. They are cheap enough from Thomann!
The bottom line is, if you play a fender style guitar with a screw in Tremolo Arm, you don?t just want to use these springs, you NEED them!