In a region of homogeneous density, a spherical embedded lens would correspond to the symmetric concentration of a spherical locality's mass into a smaller sphere (or a point) at its center. For a cosmological lens, if the universe has a non-vanishing cosmological constant Λ, then Λ is required to be the same inside and outside of the void. The metric describing the geometry within the void can be Schwarzschild or Kottler depending on whether there is a non-zero cosmological constant.