The BP2500B0402AT from Frontier Electronics is a Band Pass Filter with Frequency 2.4 to 2.5 GHz, Insertion Loss 2.5 dB, Rejection 15 to 25 dB, VSWR 2.00:1, Operating_Temperature -40 to 85 Degree C. Tags: Surface Mount, Ceramic Filter. More details for BP2500B0402AT can be seen below.