The 21.02.17 from Hytem is a Digital Phase Shifter with Frequency 2.3 to 3.8 GHz, Phase_Shift 0 to 360 Degrees, Phase Step 5.625 Degrees, Power dBm 27 dBm, Power W 0.5 W. Tags: Module with Connectors, USB Phase Shifter. More details for 21.02.17 can be seen below.