The TC0597A from Tai-Saw Technology is a SAW Resonator with Frequency 639.928 to 639.998 MHz, Centre Frequency 640 MHz, Insertion Loss 1.3 to 2.5 dB, Capacitance 2.68 pF, Voltage 3 V. Tags: Surface Mount, SAW Resonator. More details for TC0597A can be seen below.