Double Sided PCB with Rogers RO4350B Reinforce Hydrocarbon/Ceramic, Low Dk, Low CTE Laminiate for High Frequency/ Low Loss Application Number of Layer:    2 V 16 Layers (1.60mm thickness) Solder Mask:    Taiyo PSR4000, Probimer 77, Sunchemical Imagecure V Series Peelable Mask:    Peters2955 Surface Finish:    Lead Free HAL, Tin-Lead HAL, Immersion Gold, Immersion Silver, Immersion Tin, Hard Gold, Flash Gold, OSP, Carbon Keypad, Gold Finger Plating.