The MA05557 from Golledge is a SAW Resonator with Frequency 433.845 to 433.995 MHz, Centre Frequency 433.93 MHz, Insertion Loss 1 to 2 dB, Voltage 12 V, Operating Temperature -40 to 85 Degree C. Tags: Surface Mount, SAW Resonator. More details for MA05557 can be seen below.