Treatment of exhaust gases from an internal combustion engine

A porous wall-flow body suitable for use in the treatment of exhaust gases from an internal combustion engine, the body having a plurality of passages extending along its interior between a gas inlet end or face of the body and a gas outlet end or face of the body, a centrally disposed longitudinal axis through an opening in the outlet end or face into at least one of the passages being non-perpendicular to at least one tangent to said outlet face which intersects the centrally disposed longitudinal axis, an acute angle between the centrally disposed longitudinal axis and the tangent being 70° or less.