Flashing and plaster stop

After putting the windows in I had to fill the gap between the rough
opening and the window. I used a special spray foam designed to
insulate and make the gap air tight. This foam is flexible for
expansion and contraction. You can see in the picture that the foam
goes everywhere once it cures. I have to peel off the excess then
apply the flashing, or window tape. The metal is the plaster stop on
the bottom edge if the house. It simply stops the plaster from sliding
while it's still wet.