I use it to fix items with Cu wires. When fixing items, we need "softness" for the wire. Therefore, Cu material is used instead of Fe material. The price was cheap, I used Fe material, but I could not fix it well. Also, before, we purchased Cu material at the tool shop, but there were several out of stocks. I started to use Monotaro-sama, and when necessary we can purchase the necessary Cu material at a stable price.