This is a genuine set of Fender tremolo springs, set of 5, part number 0031643049 for a Stratocaster. Springs do lose some of their responsiveness over time. Replacing the springs is a good idea to keep you tremolo working properly. New springs may help solve some of the intonation problems associated with Strat trems. In general, your guitar will be more responsive and stable. Why not update your Strat now with this genuine Fender part. Made in the USA.