With the CANchecked Display MFD15 rotary knob you get the perfect rotary knob for the CANchecked Display GEN2 MFD15 (OBD2) displays. This rotary knob can be used in conjunction with the potentiometer as an additional button or function for the MFD15 GEN 2. the CANchecked rotary knob for the MFD15 GEN 2 is made of high-quality aluminum and is precisely milled.