3-1/2 in. SureCorner Flexible Corner Flashing for Window Installation (Box of 120)

2 per window. So a pack of 4 will do 2 windows. You just need them on the bottom corners

it is used between the outside of the window frame and the wood framing or block opening in the exterior wall - help to keep water out of the corners and is covered by window tape after screws are inspected - any window louvered or not should be able to use it - hope this helps

When I was buying it, I had the same question - why can I buy this in the store. The area I live in is going through one of the largest housing booms in the country but I too had to order it. I looked around at all different type of home construction/lumberyards and nobody stocks it. As a homeowner and do it yourself person I’m going to take a little bit more time than the average contractor does to bang out a project. I will say that they came very quickly when I ordered them and because I was thinking ahead it’s in an affair with what I was doing. Hope this helps.

About 1/16 of an inch, maybe a little less. Not greater than 1/16"

I installed these on window rough openings with 2x6 framing. The main focus of these is to provide a seamless corner transition of the wall plane to sill/jamb. Flashing tape handles the rest. The depth of framing doesn't matter.

No, just the two bottom corners.

Because the average joe would never think of buying these and they would sit on the shelf gathering dust.

This corner flashing is 3.5 inches deep which works well for windows. In some cases It can also be used on doors; however some doors will require a 4 and 9/16 inch sill flashing.