This product is made of imported high-purity unbleached sulfate insulating wood pulp, which is processed by high-temperature pressing. At the same time, it has undergone pure purification treatment on papermaking water, making the product have high chemical purity, high mechanical strength, excellent electrical performance, low compression coefficient, high tightness, low moisture content, and smooth surface. Thick insulating cardboard is applied to large transformers, high-voltage high-capacity transformers, reactors, transformers, and other fields as high-quality insulation materials. The thickness is above 0.50mm and packaged in flat form, with options of 0.80mm, 1.5mm, 2.00mm, 3.00mm, and 4.00mm; The external specifications are: 1000X2000mm, 1400X1100mm, 1400X2000mm, and the colors are natural (electrical cardboard) and red (red steel plate)