AKG / Crown PZM10 LL Professional Flush-Mount Boundary Layer Microphone with Line Level OutThe PZM 10 and PZM 10LL, part of the Pressure Zone Microphone line, are designed for security, surveillance, and conference table use. Since they do not look like microphones, they are inconspicuous. Each mic's tubular housing mounts in a 25 32 inch diameter hole in a ceiling panel, wall or table. The PZM 10LL has a line level output from its unterminated cable. It requires 12 to 24 V DC. Like other Pressure Zone Microphones, the PZM 10 and PZM 10LL