Fujitsu resonators (C1, C3, C4 series) feature originally developed single crystals with a high electromechanical coupling coefficient (LiTaO3: lithium tantalate, LiNbO3: lithium niobate), the result is compact packaging. Three series are available: the C3 and C4 series with built-in capacitors for high integration, for exclusive use in microcomputer clocks; and the C1 series for high precision. All series include the CHIP type device for surface mount and the SIP type device for general PC boards.