The TC0308A from Tai-Saw Technology is a SAW Resonator with Frequency 644.729 to 644.809 MHz, Centre Frequency 644.769 MHz, Insertion Loss 1.1 to 2 dB, Capacitance 2.76 pF, Quality Factor Unloaded 10417. Tags: Surface Mount, SAW Resonator. More details for TC0308A can be seen below.