The CER0821B from CTS Electronic Components is a Band Pass Filter with Frequency 2.07 to 2.21 GHz, Bandwidth 140 MHz, Insertion Loss Less than 2.5 dB, Rejection 15 to 16 dB, Power 1 to 10 W. Tags: Surface Mount, Ceramic, Ceramic Filter. More details for CER0821B can be seen below.