The AM1555B539 from Anatech Electronics is a Band Pass Filter with Frequency 1.53 to 1.59 GHz, Bandwidth 60 MHz, Center Frequency 1555 MHz, Insertion Loss 1.5 dB, Upper Rejection 58dB @ 1210 MHz. Tags: Ceramic, Surface Mount, Ceramic Filter. More details for AM1555B539 can be seen below.