It mainly divides into ceramic filters (CERAFIL) and monolithic crystal filters. MURATA using the piezoelectric characteristics of ceramic to provide light and compact filters as for AV equipment, communication equipment and other intermediate frequency equipment, and notch filter. The monolithic crystal filter (MCF) is a band-pass filter that allows specific band pass. High Q value of crystal makes it has a steep pass characteristic. Monolithic crystal filters are often used in the wireless business.