The DL4 from RN2 Technologies is a Delay Line with Frequency 300 MHz to 2.8 GHz, Group Delay 3.95± 0.1 to 4.20± 0.2 nS, Insertion Loss -4.6 to -1.9 dB, Return Loss -20 to -15 dB, Operating Temperature -55 to 125 Degree C. Tags: Surface mount. More details for DL4 can be seen below.