The D'Addario Pro Arté EJ 45 is a set of nylon/classical guitar strings. I would only use these on a guitar that is designated for nylon strings, although I don't know how they would work out on a steel string guitar. I don't own a classical guitar any more, but I used to have one when I was playing classical a bit and used these strings. The guitar that I had was a Takamine C132S
and I still have a back up pair of these strings even though I no longer own the guitar. These strings are manufactured in the United States and are a normal tension set of strings. I'm not an expert when it comes to classical or nylon strings, but these are good strings and will definitely get the job done at a low cost. I honestly haven't tried too many other sets of classical strings, and probably none other from D'Addario, but I've certainly used other acoustic and electric strings from D'Addario and of course like many I've been a big fan. The Pro Arté EJ 45 have a very clean overall feel that will make your guitar as easy to play as it will allow. I don't think it's possible to go too wrong with these strings as they are very well made and won't cost you much at all. You might think that classical strings are a bit more expensive than your average electric or steel acoustic strings, but they're in the same ballpark and these are definitely right in there with the rest of classical strings when it comes to price. You can probably get some pretty expensive nylon strings if you're a true professional and need the best of the best, but for those looking for a good pair of classical/nylon strings for cheap, these will do the job.