The Metal Core PCB of the Thermal PCB can be aluminum (aluminum core PCB), copper (Copper Core PCB or a Heavy Copper PCB) or a mixture of special alloys. Metal core PCB or IMS (Insulated Metallic Substrate) Circuit Boards are an excellent alternative to standard circuit boards, if the circuit boards are exposed to large mechanical loads, or a high level of dimensional stability is required, or high temperatures must be conducted away from power components or LED's. The most common is an aluminum core PCB.

The thickness of metal cores in PCB base plates is typically 30 mil - 125 mil, but thicker and thinner plates are possible.

MCPCB copper foil thickness can be 1 - 30 oz.