Based on different base material, there're three basic types but not limited to: FR-4/3/2 PCB, CEM-3 PCB, Metal Core PCB and Special PCB series (such as Ceramic PCB). For FR-4 PCB, right now, we just class it into S/S PCB, 2 Layers PCB, Multi-Layers PCB (20 layers). For MCPCB, which full name is Metal Core Printed Circuit Board, there're single layer MCPCB, double layers MCPCB and double sided MCPCB (2 layers on each side). Special PCB, in fact, should be sorted to above two tapes, but considering special requirements, so we list it seperated. Right now, we can make RF boards (Rogers, Taconic materials), Heavy Copper PCB (4~20 OZ/ft2), Ceramic PCB, HDI, and so on.