4 layer-blind-hole-pcb. 4 layer Blind via holes . the smallest via holes are 3 mil. and 4 mil. and the smallest pads gap are 1.5mil. copper line to line spacing is about 1.3mil. we make the blind via holes pcb board. from 4 layer to 50 layer. it’s higher pcb quality.
Please send us your pcb gerber files. and the pcb Stackup info and the materials request. let’s have a quote.