The invention relates to a flashing for use with siding panels possessing an interior and an exterior surface, and a perimeter surface having a predetermined sectional width, and includes a first, a second, and a third portion, and a first and a second non-perforated, generally planar transition portion, each portion having an interior and an exterior surface wherein (a) the portion continues to the first generally planar transition portion and forms a first angle there between; wherein (b) the first generally planar transition portion continues to the second portion and forms a second angle there between; wherein (c) the second portion continues to the second generally planar transition portion and forms a third angle there between; and wherein (d) the second generally planar transition portion continues to the third portion, which is substantially parallel to the first portion, and forms a fourth angle there between. The angle between the various portions can be modified to facilitate water migration away from a siding panel placed in contact therewith, and the transverse distance of the transition portions can be varied, preferably to approximately 50% of the siding sectional width.