Boya Directional On-camera Microphone BY-BM3032 Ideal for camera, camcorder and audio recorder etc. Super-cardioid professional shotgun microphone. 20Hz to 20kHz wide range frequency response. Three step high pass filter (0Hz, 75Hz, 150Hz). Three position level control (-10dB, 0, +20dB). Automatic power on-off function. Safety Channel function for right channel. High frequency boost function. 3.5mm headphone output for real-time monitoring. Powered by a pair of AA batteries for about 30 hours use.