The ACTR310/310.0/TO39 from Advanced Crystal Technology is a SAW Resonator with Frequency 309.925 to 310.075 MHz, Centre Frequency 310 MHz, Insertion Loss 1.4 to 2 dB, Capacitance 2.2 to 2.8 pF, Quality Factor Loaded 1950. Tags: Drop In, SAW Resonator. More details for ACTR310/310.0/TO39 can be seen below.