ArraySolutions PowerMaster QRP Coupler - Very few of these QRP couplers were made. This QRP coupler is mounted in a small aluminum case with SO239 UHF connectors. This coupler accurately measures power from 50 milliwatts to 150 watts from 1.8-54 MHz. And accurately measures VSWR from 100 milliwatts to 150 watts from 1.8-54 MHz. It can be used with either the original PowerMaster display, where you set the trim to +9 and mentally divide the reading by 10 (instead of watts, it now is reading deciwatts), or with the PowerMasterII display where you select “QRP HF’ as the sensor inuse, set the trim to 0, and the power is indicated directly. The photo of the displays is of two QRP couplers in series feeding a dummy load on 6 meters. The upper display is an original PowerMaster and so the reading must be divided by10. The lower display is a PowerMasterII which reads out the power directly. A display is NOT included. The coupler is NIST-cal’d.