Group 1 - The company, Wenzhou Hongfeng (300283.SZ), is involved in the research, manufacturing, and production of hard alloy products [2] - The company's hard alloy rods are utilized by downstream customers for further processing into PCB drill bits and drill needles [2]

Group 1 - The company responded to an investor inquiry regarding whether its PCB drill bit customers include Shenghong Technology and mentioned that its coverage of the top twenty global PCB customers exceeds 80% [2]