The MPI-46W & MPI-47 “screamers” are a complete and advanced range of piezo devices. Patented technology provides a powerful sound output with a minimum of current consumption. This makes the piezo “screamer” suitable for use with many of today’s control panels, even those that provide only limited power for audible devices. Unlike a conventional speaker, a piezo is a crystal type resonator, which provides a broad sound dispersion and a longer service life. Piezos emit a piercing high frequency sound, which is very intense close-up – ideal for smaller houses or stores, apartments or pre-alarm applications. The MPI-46W and the MPI-47 are housed in attractive enclosures for surface mounting. The MPI-47B, 47C and 47E provide a variety of mounting options: - MPI-47B is a small round device which can be easily installed on a wall or a ceiling, using the metal bracket. - MPI-47C is designed for mounting directly into a dropped ceiling and includes an attractive circular faceplate for an easy and neat installation. It can also be flush-mounted in any wall or ceiling. - MPI-47E fits directly into a NEMA standard electrical box of at least 2.0" (5.1 cm) width. A plastic (PVC) box of 2.0" (5.1 cm) x 3.5" (8.9 cm) is recommended. If a metal box is used, it should be at least 2.1" (5.3 cm) wide. The device is fitted with an attractive faceplate. The MPI-46W provides both a bell and a pulsating horn sound. The other products in the range provide a single high/low sound.