... , GPS), 1 only to the rear portion of the helmet Bluetooth headset, a total of 4 device, the otherCable connection 1 way ... -01, 1 only to the rear portion of the helmet Bluetooth headset, the other a wired connection 1 way device.Two, implement ... a connection can be ensured no matter the function, GPS's voice can be heard, if want to maintain radio time ...