This worked perfectly. Using the development branch for my NodeManager library and changing my 'void before()' to the following code presented the proper unit_of_measurement to my Home Assistant controller for the pressure sensor. Thanks for the assistance. void before() { /********************************** * Configure your sensors **********************************/ // send unit prefixes to controller (i.e. V, A, hPa, %, etc.) nodeManager.setSendUnitPrefix(true); // let controller know ambient pressure sensor reports in hPa ambient.children.get(3)->setUnitPrefix("hPa"); // report ambient measurements every 15 minutes ambient.setReportIntervalMinutes(15); // report battery level every 60 minutes battery.setReportIntervalMinutes(60); // report radio signal level every 10 minutes signal.setReportIntervalMinutes(10); // only a pseudo SR_TX_RSSI and SR_UPLINK_QUALITY are available for NRF24 // radio. All other methods return as INVALID. signal.setSignalCommand(SR_UPLINK_QUALITY); // call NodeManager before routine nodeManager.before(); }