Hello, are you asking about the pin of the electron tube? It depends on the specific model and manufacturer. Generally speaking, Xiao Jiu pins; Xiaoqiao is tin-plated iron (not ordinary iron); Such as the common 6n1; 6N26A26K4 ... but there are also gold-plated pipes, such as 6N 1 1 in Beijing Shuguang, and other pipes, such as the common eight-legged ones, are generally tin-plated on the outside of copper or iron, and of course there are also gold-plated pipes, such as Tianjin Quanzhen 2A3300B. ........

In short, there are many schools in this circle, some pursue the management of famous schools, resist the content, and some pursue the import supplement. I'm DIYD's hands-on, and I can't help it if I have less money. I hope you and I are in the same school. Nice talking to you.