Transmits signals independent of the mains, with sequences of bright flashing lights, different coloured LEDs and an acoustic alarm which can be switched on/off. A special connection cable in the housing of the RF blink lamp allows the temporary supply by a regular 9 V battery or the special Humantechnik rechargeable battery A-2995-0. You can charge the rechargeable battery when using together with the power supply unit. If you take away the RF blink lamp from the electric network, the RF blink lamp will be supplied by the according battery only.