- SMD / SMT package: DFN12 4.0 X 3.0 mm 0.50mm pitch. - Adapter pcb board for breadboard prototyping and module building. - PCB with solder mask layer to minimise solder bridges during soldering. - For connectors with a 0.1-inch pitch, not included. Breadboard compatible. - Bottom copper with a small proto area: 2x 3x3 pads. - A small ground plane under the chip is available with one pad connection.