  R7-branes are a class of recently discovered non-supersymmetric real
codimension-two duality defects in type IIB string theory predicted by the
Swampland Cobordism Conjecture. For type IIB realizations of 6D SCFTs with
$\mathcal{N} = (2,0)$ supersymmetry, wrapping an R7-brane "at infinity" leads
to a topological operator associated with a zero-form charge conjugation
symmetry that squares to the identity. Similar considerations hold for those
theories obtained from further toroidal compactification, but this can be
obstructed by bundle curvature effects. Using some minimal data on the
topological sector of the R7-branes, we extract the associated fusion rules for
these charge conjugation operators. More broadly, we sketch a top down
realization of various topological operators / interfaces associated with
$\mathsf{C}$, $\mathsf{R}$, and $\mathsf{T}$ transformations. We also use
holography to provide strong evidence for the existence of the R7-brane which
is complementary to the Cobordism Conjecture. Similar considerations apply to
other string-realized QFTs with symmetry operators constructed via
non-supersymmetric branes which carry a conserved charge.
