Core, prepreg and copper are different rowsCore, prepreg and copper are different rowsCured core dielectricA double-sided core carries two copper layers.Prepreg: glass + resinStyle + RC + resin systemPressed thickness depends on construction.Finished board = copper + dielectric + declared coating allowanceDo not count copper inside a laminate thickness twice.Engineering illustration. A glass style such as 1080 does not identify one universal cured thickness.