The RO3118A-1 from Murata is a SAW Resonator with Frequency 317.925 to 318.075 MHz, Centre Frequency 318 MHz, Insertion Loss 1.5 to 2 dB, Capacitance 2.9 pF, Quality Factor Loaded 2000. Tags: Surface Mount, SAW Resonator. More details for RO3118A-1 can be seen below.