... fr4 pcb 4-layer rigid pcb manufacturers and suppliers with professional copper pcb fr4 pcb 4-layer rigid pcb factory, we are ... -R015 Number of Layers: 4-Layer Base Material: FR-4 Copper Thickness: 1oz Board Thickness: 1.6mm Min. Hole Size: 4mil ... ,Yellow,Blue,Orange,Purple Laser drill hole size: 0.1mm Copper Weight Tolerance: ± 0.25oz Board Thickness Tolerance: ±10% 100% function ...