de10n_sfp_shield

It works perfectly, especially with differential pair transmission. Layer stack guide is helpful designing diffpairs. ( https://www.pcbway.com/blog/Engineering_Technical/stackup___pcbway.html ) BTW, 0.11mm prepreg of 1.6 or 1.2mm 4-layer 1oz copper structure is a little bit too thin to achieve 100 ohm differential impedance matching in regular 0.2mm wiring. We can use 1.0mm or thinner structure to get 0.175mm prepreg but we'll be happy if there any option to get thicker prepreg such as 0.2mm when we use 1.2mm and 1.6mm structure.