Go wireless in your classroom with plug and play simplicity. Connect the wireless transmitter to any analog audio source through 1/8" stereo mini plug and transmit audio via dedicated FM signal, up to 300 feet, to a nearly unlimited number of wireless headphones. With 4 different color-coded frequencies, you can easily switch between them and with additional transmitters you can have up to 4 different channels of audio broadcasting simultaneously! You'll get everything you need with this system, including one wireless transmitter, 12 wireless headphones and a lockable case to carry and store your listening center. It's the perfect solution for all multimedia labs and classrooms. This 12-Station Wireless Listening Center Includes: (1) Wireless Multi-Channeled Transmitter (W900-Multi) (12) Wireless Multi-Channeled Headphones (W901-Multi) (2) AC Power Adapter (W980) for use with transmitter and headphone charging (NOTE: A single AC power adapter is only capable of charging 6 wireless headphones at one time. Do not combine two 6-way charging cables with one AC Cord). (2) 6-way charging cables (W990) for wireless headphone charging (1) Lockable Carry Case (lock not included)