EN
Let F = ind lim Fₙ be an infinite-dimensional LF-space with density dens F = τ ( ≥ ℵ ₀) such that some Fₙ is infinite-dimensional and dens Fₙ = τ. It is proved that every open subset of F is homeomorphic to the product of an ℓ₂(τ)-manifold and $ℝ^∞ = ind lim ℝ ⁿ$ (hence the product of an open subset of ℓ₂(τ) and $ℝ^∞$). As a consequence, any two open sets in F are homeomorphic if they have the same homotopy type.