1. Good flatness, smooth surface, no pits, standard thickness tolerance. 2. Low water absorption, good moisture resistance and good dielectric performance. 3. stable electrical insulation performance, in dry or wet conditions have good electrical performance. 4. high mechanical strength, good machinability.Drilling, drilling, processing, cutting. 5. Good machinability. 6. Stable electrical performance at high temperature. 7. High mechanical and dielectric properties.