This method is for a 0-degree (straight) probe. Depending on which type of probe is selected, a specific DGS curve, determined and produced by the probe manufacturer, is utilised in the flaw detector UT set. From the probe data sheet, the dB difference between the infinite reflector and the equivalent 3mm FBH (eFBH) at the maximum sound path, is noted. This is the Delta V (ΔV) value that is added to the set up. However, this is not a value added as an increase in gain over the DGS curve (i.e., not an up gain). It is an increase in dB level, purely to be used as a search tool, that does not affect the reference sensitivity and therefore does not impact the recording levels of any indications.