This is our own PCB heatbed design. It supports both 12V and 24V power systems, making it a flexible solution to any 3D printer design which calls for a 20cm x 30cm print area.
The back side of the board has been extended in order to make it easier and more reliable to connect to. Slots at the rear of the board are meant to zip-ties to secure power wires (see example photo of assembled unit). The bed can be used with either 12V or 24V power supplies by selectively jumpering the points labeled on the board. In 12V systems, the board will draw approximately 9A (110W), which makes it suitable for use with most reprap control boards. There is a mounting hole for a traditional thermistor to be taped to the back side of the board, as well as pads for a 0402 SMT thermistor if you wish.