The WHK4-600-700-60-4000-20 from Wainwright Instruments is a RF High Pass Filter with Frequency 600 / 700 MHz to 4 GHz, Insertion Loss 0.4 to 0.5 dB, Power 20 W, Rejection 60 dB, VSWR 1.50:1. Tags: Module with Connectors, Lumped Component Filter. More details for WHK4-600-700-60-4000-20 can be seen below.