Sennheiser EW 152 G3. Total Harmonic Distortion (THD): 0.9 %, Signal-to-Noise Ratio (SNR): 110 dB, Frequency response: 80 - 18000 Hz. Headphone connectivity: 3.5 mm. Connectivity technology: Wired & Wireless. FM band range: 516 - 865 MHz. Battery type: AA