The HDF315M1 from Shoulder Electronics is a Band Pass Filter with Frequency 314.68 to 315.31 MHz, Bandwidth 0.63 MHz, Center Frequency 315 MHz, Insertion Loss 2.6 dB, Ripple 0.6 to 1.5 dB. Tags: Surface Mount, RF SAW Filter. More details for HDF315M1 can be seen below.