This Router App adds nodes to the Node-RED Router App and works only after the Node-RED Router App is installed.
Splunk HEC is an HTTP event collector. Adding this router app to the router will add the splunk hec metric and splunk hec nodes to the cloud palette. These nodes enable contribution with Splunk tools (www.splunk.com) and allow Node-RED to publish a payload to Splunk's HTTP Event Collector. See more information in the official documentation: https://flows.nodered.org/node/node-red-contrib-http-event-collector