Rockville RFH3 Wireless Universal Infrared IR Car Headphones for Any Car Monitor Rockville RFH-3 Dual Channel IR Headphones. Foldable design for Travel convenience and easy storage. Comfort control leatherette ear surround. Dual channel function capable (A/B). Improved acoustic performance. 40mm Mylar dome speaker built in. Extended bass response. Impedance: 32 Ohms &plusmn;10%. Effective distance: 10 meters (max.). Light weight design for wearing comfort. Auto muting on headphone. Auto power off when no signal. Specifications: A Frequency range 17-23,000 Hz. A Channel, IR_OUT_L:2.8 MHz. A Channel, IR_OUT_R:2.3MHz. B Channel, IR_OUT_L:3.8 MHz. B Channel, IR_OUT_R:3.8 MHz. B Channel, IR_OUT_R:3.2MHz. Sensitivity 96 dB. Modulation high frequency. Power supply 2X1.5V. Battery R03 (AAA) 48h (Batteries not included). Weight 160 gr. (excl. batteries).