The HDF903A1 from Shoulder Electronics is a Band Pass Filter with Frequency 900 to 907.5 MHz, Bandwidth 7.5 to 17.7 MHz, Center Frequency 903.75 MHz, Insertion Loss 3.2 dB, Ripple 1.0 to 2.0 dB. Tags: Surface Mount, RF SAW Filter. More details for HDF903A1 can be seen below.