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[T. Bhanja$^{(a)}$, N. Srinivas$^{(a)}$, R. P. Malik$^{(a,b)}$]{}\
$^{(a)}$ [*Physics Department, Centre of Advanced Studies,*]{}\
[*Banaras Hindu University, Varanasi - 221 005, (U.P.), India*]{}\
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$^{(b)}$ [*DST Centre for Interdisciplinary Mathematical Sciences,*]{}\
[*Institute of Science, Banaras Hindu University, Varanasi - 221 005, India*]{}\

[**Abstract:**]{} We exploit the key concepts of the augmented version of superfield approach to Becchi-Rouet-Stora-Tyutin (BRST) formalism to derive the superspace (SUSP) [*dual*]{} unitary operator (and its Hermitian conjugate) and demonstrate their utility in the derivation of the nilpotent and absolutely anticommuting (anti-)dual BRST symmetry transformations for a set of interesting models of the [*Abelian*]{} 1-form gauge theories. These models are the one (0+1)-dimensional (1$D$) rigid rotor, modified versions of the two (1+1)-dimensional (2$D$) Proca as well as anomalous gauge theories and 2$D$ model of a self-dual bosonic field theory. We show the [*universality*]{} of the SUSP [*dual*]{} unitary operator and its Hermitian conjugate in the cases of [*all*]{} the Abelian models under consideration. These SUSP dual unitary operators, besides maintaining the explicit group structure, provide the alternatives to the dual horizontality condition (DHC) and dual gauge invariant restrictions (DGIRs) of the superfield formalism. The derivation of the [*dual*]{} unitary operators and corresponding (anti-)dual BRST symmetries 