Remark 4.5.2.5. Let $F_0: \operatorname{\mathcal{C}}_0 \rightarrow \operatorname{\mathcal{C}}$ and $F_1: \operatorname{\mathcal{C}}_1 \rightarrow \operatorname{\mathcal{C}}$ be functors of $\infty $-categories. Then there is a canonical isomorphism of simplicial sets
\[ (\operatorname{\mathcal{C}}_{0} \times ^{\mathrm{h}}_{\operatorname{\mathcal{C}}} \operatorname{\mathcal{C}}_1)^{\operatorname{op}} \simeq \operatorname{\mathcal{C}}_{1}^{\operatorname{op}} \times _{\operatorname{\mathcal{C}}^{\operatorname{op}}}^{\mathrm{h}} \operatorname{\mathcal{C}}_{0}^{\operatorname{op}}. \]