TR50 Mic Head Specifications: • Size: .18" X .300" X .55" (4.57 X 7.6 X 14 mm) [Does Not Include Strain Relief] • Type: Omni-Directional Electret Condenser • Frequency Response: 40-16000 Hz • Noise Level: 26db Equivalent To Spi • Maximum Spl: 134db • Output Level: -57db • Nominal Impedance: 3000ohm • Operating Voltage: 1.5VDC • Current Drain: 20-30 Microamps • Color: Standard: Black Special Order: Gray, Flesh/Tan, White • Bias: Positive