The D3-40001/40002/40003 from Crane Aerospace & Electronics is a Directional Coupler with Frequency 10 to 500 MHz, Coupling 20.25 dB, Coupling Variation ±0.25 dB, Directivity 20 dB, Average Power 3 W. Tags: Flatpack, Drop-In. More details for D3-40001/40002/40003 can be seen below.