the t.bone Tour Guide Talkback TM, Tour Guide Talkback Transmitter, System component with return channel (switchable), 20 Switchable channels in the UHF range 863 - 865 MHz, Automatic synchronisation with receivers in a group, LC-Display, Built-in lithium-polymer battery, Charging time: approx. 7 hours, Operating time: approx. 17 hours, Micro USB charging contact, 3.5 mm mini jack socket for clip-on microphone, Microphone unit with additional input (3.5 mm) for media player, Lanyard included, Weight of the transmitter: < 50 g, Housing colour: White, Suitable charging station: Article no. #386332# (not included)@+*Note:* Not compatible with transmitters / receivers of the t.bone Tour Guide Mini series@+@+