Shure MX391W-A/C Microflex Condenser Boundary Microphone Cardioid - WhiteEquipped with features like programmable, silent membrane switches, Logic inputs and outputs, and LED indicators, micro flex boundary microphones are the high quality solution for a range of applications such as altars, boardrooms and distance Learning centers. Flat frequency response across the vocal range for uncolored sound. Sleek, low profile design for unobtrusive appearance Balanced, transformer less output for increased immunity to noise over