Product Detail Cartridge Type: Permanently Biased Condenser Directional Polar Pattern: Cardioid/Omnidirectional Frequency Response: 20-20,000 Hz Phantom Power: 48 Vdc± 4 Vdc (IEC-268-15/DIN 45 596), positive pins 2 and 3 . The "Shure KSM141SL Dual Pattern Condenser Microphone Matched Pair" is best product for you. We recommended Shure KSM141SL Dual Pattern Condenser Microphone Matched Pair