This is a 2 layer alumimum PCB for LED industry. A Metal Core Printed Circuit Board (MCPCB), or a thermal PCB, is a type of PCB that has a metal material as its base for the heat spreader portion of the board. The purpose of the core of an MCPCB is to redirect heat away from critical board components and to less crucial areas such as the metal heatsink backing or metallic core. Base metals in the MCPCB are used as an alternative to FR4 or CEM3 boards.