博深股份：子公司金牛研磨有生产用于抛光印刷电路板（PCB 板）的大卷砂带产品

Group 1 - The company, Boshen Co., Ltd. (002282.SZ), reported that its subsidiary, Jinniu Grinding, produces large rolls of sandpaper specifically for polishing printed circuit boards (PCBs) [2] - The annual sales revenue from the sandpaper products is approximately 2 million yuan [2] - The sandpaper is sold to downstream converters who process it into finished products for PCB polishing [2]