Blue tooth earphone board

Layers   6L
Structure:2R+2F+2R
Thickness  0.6mm
Out Layer Copper Thickness: ⅓ OZ
Inner Layer Copper Thickness:⅓ OZ
Min hole size 0.2mm
Min Line Width/Space: 3mil
Surface finish :ENIG
Product use: JBL Headset
Difficulties:high quality of impedance matching