4.4mm PCB with blind vias and countersink holes

This is a VERY special 4 Layer PCB with thickness 4.4mm, and blind vias from L1-L2,L3-L4.

Countersink holes :top hole size 1.0mm, bottom hole size 1.6mm  min hole is only 0.3mm

Matt Black solder mask. via in pad.

We can make nearly all types of special PCBs,top thermal conductivity PCBs,HDI ,RF,Rigid-flex PCBs. We do what others are unable to do .

Here is the stackup:

L1 

Core 0.365mm

L2

PP FR4 bare core 3.065mm

L3

Core 0.365mm

L4

Here is the countersink holes.