The DR1-4339 from ECS Inc. International is a SAW Resonator with Frequency 433.845 to 433.995 MHz, Centre Frequency 433.92 MHz, Insertion Loss 2 dB, Capacitance 1.7 to 2 pF, Quality Factor Loaded 2100 Q. Tags: Drop In, SAW Resonator. More details for DR1-4339 can be seen below.