The P{ET-lexA::GAD.GU} entry in FlyBase is used to denote the transgenic construct present in an insertion when it is known that the inserted element is an enhancer trap construct that encodes the lexA::GAD driver and that it was generated by homology assisted CRISPR knock-in (HACK) into a GAL4 enhancer trap line, but where the exact nature of the enhancer trap construct present in the progenitor GAL4 insertion line is not known or was not specified.