Telex SR-50 SoundMate Single Frequency Personal Reciever (Ch E 72.5) Provides clear reception and the simplicity of a fixed channel. Recessed headphone jack provides extra protection for earphone connections. Ergonomic raised volume control knob make level adjustments easily accessible by feel. This economical receiver operates on one of 17 fixed narrow-band frequencies in the 72-76 MHz band. Two AA batteries give up to 30 hours continuous battery life.