SMALL MEMBRANE CONDENSER MICROPHONE Miniature condenser microphone with gooseneck and adapter designed for brass instruments. Polar pattern: cardioid. Frequency response: 40Hz - 20KHz. Impedance: 250Ohm Off-axis attenuation: > 20dB. Max SPL: 135 dB. Sensitivity: 5.8 mV/Pascal. APS-910 phantom adapter included. Gooseneck clip, foam and carrying bag. Download complete specifications sheet in pdf at this link... http://www.audixusa.com/docs_12/specs_pdf/ADX20i:ADX20iP_v4_0517.pdf