Hi, Which is the minimum PCB thickness per layer pairs you have ever used for a multilayer (10 or more layer) board ? 3 mil for prepreg and 3 mil for PCB thickness could be a feasable dimension for a hitech PCB manufacturing house ? If yes, who is the manufacturer ? Have you ever measured the epsilon of the prepreg ? thx, Vasile -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist