Window Shelf Sill Extender

I wanted to be able to place plants on the window that have more sun, but the window sills were too small. I designed this to increase the shelf/sill  area to accommodate potted plants.  It holds onto the existing sill, avoids the skirt when bracing against the wall - and I added adjustment screws so that it could sit level or tilted towards the window for the stability of whatever is placed upon it.