The CER0543B from CTS Electronic Components is a Band Pass Filter with Frequency 2.5 to 2.69 GHz, Bandwidth 194 MHz, Insertion Loss Less than 3.2 dB, Rejection 15 to 27 dB, Power 3 to 30 W. Tags: Surface Mount, Ceramic, Ceramic Filter. More details for CER0543B can be seen below.