三变科技：公司主营业务为各类型变压器的研发、生产及销售，主要用于电力转换、传输，目前有出口北美洲国家

Group 1 - The company, Sanbian Technology, specializes in the research, production, and sales of various types of transformers, primarily used for power conversion and transmission [2] - The company has confirmed that it exports products to North American countries [2]