Peavey ALS 72.9 Mhz Assisted Listening System Transmitter And Four Receivers With Ear Buds Features: Peavey ALS 72.9 Mhz Assisted Listening System Transmitter And Four Receivers With Ear Buds Frequency Response 100Hz - 15 KHz, +/- 3dB Signal-to- Noise Ratio 60dB Total Harmonic Distortion <0.5% RF Carrier Frequency between 72-76 MHz Frequency Stability +/- 0.005% Modulation FM +/- 75KHz max Operating Range Up to 300 ft. line of sight Mic Input - Connector: ¼" phone jack, Impedance: low impedance, unbalanced, with 9V DC at 1 mA for condenser mic. Line Input - Connector: ¼" phone jack, Impedance: 100 K, unbalanced. Power Output - 80,000 uV @ 3 meters. Controls - Power ON/OFF, audio input gain adjust Indicators - Power ON LED, Audio Modulation LED Antenna - Permanently mounted telescoping whip Power Requirement - 9V DC, regulated @ 200 mA, AC/DC adapter provided Dimensions - 220 x 121 x 43mm Weight - 19.5 oz (600g) Controls - Combination VOLUME/ON-OFF wheel Audio Output - 250 mW max into 16 ohms Connectors - 3.5mm mini jack for earphone output Earphones - Mini binaural ear buds Antenna - Integral with earphone cord Indicators - LED power on indicator Sensitivity - 2 uV for 12 dB Sinad with squelch defeated, Squelches at 10 uV for min. 50 dB S-N ratio Mute Threshold - 8-10 uV Power Requirement - (2) AA Batteries Battery Life - 17-20 hours with alkaline battery Dimensions - 110 x 60 x 20 mm Weight 2.75 oz without batteries (80g)