The Shure BETA 181/BI Figure 8 Compact Side-Address Instrument Microphone is a durable, small-diaphragm electret condenser microphone with an interchangeable capsule design. The Beta 181/BI ships with a figure-8 capsule for mono drum overhead and dual instrument sound source applications, as well as Blumlein stereo technique (BETA 181/BI pair). The microphone features a wide frequency response and rugged construction, making it ideal for the stage and recording studio. The Beta 181/BI FIGURE 8 Compact Side-Address Instrument Microphone from SHURE is a durable, small diaphragm, electret condenser microphone with an interchangeable capsule design. The beTA 181/BI ships with a FIGURE 8 cartridge for sound source applications with mono and dual instrument drum overdrives, as well as Blumlein stereo technique (pair of Beta 181/BI). The microphone features a wide frequency response and rugged construction, making it ideal for stage studio and recording applications..PZA MORE SPECS