Let $X$ be an $n$-dimensional paracompact strictly $K$-analytic space and $\overline{L}_{1},...,\overline{L}_{n}$ formally metrized line bundles on $X$. Let $\mathfrak{X}$ be a formal model of $X$ on which there exist formal models $\mathfrak{L}_{1},...,\mathfrak{L}_{n}$ of $\overline{L}_{1},...,\overline{L}_{n}$. The existence of such a formal model follows from Remark 3.2. We then define

$$c_{1}(\overline{L}_{1})\wedge...\wedge c_{1}(\overline{L}_{n}):=c_{1}(\mathfrak{L}_{1})\wedge...\wedge c_{1}(\mathfrak{L}_{n}).$$

Note that this definition is independent of the choice of $\mathfrak{X}$ and $\mathfrak{L}_{1},...,\mathfrak{L}_{n}$ by the projection formula. If the metrics on $\overline{L}_{1},...,\overline{L}_{n}$ are semipositive then $c_{1}(\overline{L}_{1})\wedge...\wedge c_{1}(\overline{L}_{n})$ is a positive measure.