... This form is of my company's process capacity for your reference, for more messages, pls contact with us freely!ItemSpecification ... Pitch 20 milMin Pad Space 4mil(SMT)Plating Copper Thickness15um Hole Hole Size0.25mm--6.2mmHole Position Tolerance±0.1mmPTH/NPTH ... pass for the first time,+/-2%(tolerance) Certificate SGS,ISO,ROHS,UL, Welcome to visit WALBOND ! 4 Layer PCB with buried&blind hole