... T0.2mm 2. Immersion gold 3. Application moblile phone keyboard with competitive price. 1. PI material, ... copper, board T0.2mm2. Immersion gold3. Application moblile phone keyboard with competitive price5. Certificate: ROHS, UL, ... FR-4,FR-4- TG170/TG180, Halogen Free,Rogers,Arlon,Taconic,Isola,PTFE, Bergquist 2). Surface Treatment ... high pcb at the soonest. mobile phone keyboard 4 layer pcb board China