The ESL5459A2 from Eclipse MDI is a Limiter with Frequency 5.4 to 5.9 GHz, CW Flat Leakage 16 dBm, CW Flat Leakage 0.04 W, Peak Flat Leakage 18 dBm, Peak Flat Leakage 0.06 W. Tags: Module with Connectors, PIN-Schottky Diode. More details for ESL5459A2 can be seen below.