Surface Acoustic Wave (SAW) vibration only occurs on the surface of the quartz crystal chip allowing it to generate frequencies that ranges from several hundred MHz up to the GHz range. Bulk Acoustic Wave (BAW) associated AT type quartz crystal chip has the top surface and bottom surface of the crystal chip move in opposite directions allowing it to only cover frequencies ranging up to several hundred MHz. Epson’s SAW product line-up includes SAW resonators, SAW filters and SAW oscillators.