The ATEK821P4 from ATEK MIDAS is a Tunable Filter with Tunable Frequency 1 to 2.5 GHz, Bandwidth 1500 MHz, Rejection 50 dBc, Insertion Loss 2.5 dB, Supply Voltage 3 to 5.5 V. Tags: Surface Mount, Digitally Controlled. More details for ATEK821P4 can be seen below.