Hamilton Buhl Wireless Listening Center, 6 Station with Headphones and Transmitter, Multi Frequency Go Wireless in your classroom with plug and play simplicity The W906-MULTI is a 6 person Wireless Listening Center perfect for all multimedia, lab and classroom applications. Each system includes one transmitter and six wireless headphones The entire system can be switched between 4 different frequencies with easy color-coded switches Add additional transmitters and you'll have up to 4 different channels of audio simultaneously. (1) AC cord for use with transmitter and headphone charging (1) 6-way cable for wireless headphone charging Multi-channel wireless headphones No antenna on headphone Up to 35 hours of operating time between charges, with 12 to 14 hour charge time Superb sound quality without wires or interference Powered by classroom friendly internal NiMH battery Switchable between 4 frequencies Once 6-way cable to charge headphones with one AC cord Range:  300 feet 4 switchable FM frequencies <ul class="a-unordered-list a-vertical"> 72.500 MHz - Blue 72.100 MHz - Yellow 72.900 MHz - Green 74.700 MHz - Orange Dedicated FM channels Color-coded frequency switches AC cord for use with transmitter and headphone charging Superb sound without cords or wires - no interference from other electronic equipment Listen with an infinite number of headphones on one frequency with one transmitter