〇: It means that the content of the hazardous substance in all homogeneous materials of the part is below the limit requirement specified in
the currently valid edition of GB/T 26572.
X: It means that the content of the hazardous substance in at least one of the homogeneous materials of the component exceeds the limit
requirement specified in the currently valid edition of GB/T 26572. The content of the hazardous substance in the component is in the
RoHS exemption list, and meet the environmental protection requirements of the EU 2015/863 RoHS Directive.