Standard Stackup Impedance Calculator 1.378mil BodyUp 2.7559mil FR4 Prepreg 1080 4 2.7559mil FR4 Prepreg 1080 4 1.378mil None 14.1732mil FR4 Core 4.5 1.378mil None 2.7559mil FR4 Prepreg 1080 4 2.7559mil FR4 Prepreg 1080 4 1.378mil BodyDown