Let A be a C∗-algebra, K
the Pedersen ideal of A, and Γ(K) the two-sided multipliers of K under the
κ-topology. In this paper a study is made of the strong bidual of Γ(K), which we
denote by Γ(K)′′. Here it is shown that the Arens products in Γ(K)′′ are well defined
and coincide, and therefore make Γ(K)′′ a ∗-algebra; moreover, if A is a
PCS-algebra or has a σ-compact spectrum, it is shown that Γ(K)′′ is a metrizable
b∗-algebra which is isometrically *-isomorphic to the Cartesian product of
W∗-algebras.