The ACTR390/390.0/TO39 from Advanced Crystal Technology is a SAW Resonator with Frequency 389.85 to 390.15 MHz, Centre Frequency 390 MHz, Insertion Loss 1.2 to 1.6 dB, Capacitance 2.05 to 2.65 pF, Quality Factor Loaded 1600. Tags: Drop In, SAW Resonator. More details for ACTR390/390.0/TO39 can be seen below.