  We discuss observations of pseudostreamers and their 3D magnetic
configuration as reconstructed with potential field source surface (PFSS)
models to study their contribution to the solar wind. To understand the outflow
from pseudostreamers the 3D expansion factor must be correctly estimated.
Pseudostreamers may contain filament channels at their base in which case the
open field lines diverge more strongly and the corresponding greater expansion
factors lead to slower wind outflow, compared with pseudostreamers in which
filament channels are absent. In the neighborhood of pseudostreamers the
expansion factor does not increase monotonically with distance from the sun,
and doesn't simply depend on the height of the pseudostreamer null point but on
the entire magnetic field configuration.
