I got these to replace worn, often corroded, bridge saddle intonation adjustment screws. I had been refurbishing the originals, but it's a messy, time-intensive process and the results can vary depending on how bad the screws are. I've found that unless it's a unique, vintage instrument it's usually more cost effective for the time to just buy a replacement.Two things I really liked about these from Musiclily: the black oxide coating was uniform on all 10 screws, AND they weren't covered with anything sticky or oily that I had to clean off before installing. However, they're a little pricey at around a dollar each. If you think you're going to ever need more than 10 you can definitely save money buying in bulk elsewhere, but just know the quality of the black oxide finish can vary widely when going that route.