The WHK4-40-45-60-1000-20 from Wainwright Instruments is a RF High Pass Filter with Frequency 40 / 45 MHz to 1 GHz, Insertion Loss 0.5 to 0.8 dB, Power 20 W, Rejection 60 dB, VSWR 1.50:1. Tags: Module with Connectors, Lumped Component Filter. More details for WHK4-40-45-60-1000-20 can be seen below.