The TC0645A from Tai-Saw Technology is a SAW Resonator with Frequency 503.930 to 504 MHz, Centre Frequency 503.965 MHz, Insertion Loss 1.9 to 2.2 dB, Capacitance 3.32 pF, Voltage 12 V. Tags: Surface Mount, SAW Resonator. More details for TC0645A can be seen below.