It is about 25 stitches wide, and the front bit is just a row or two longer than my biggest hook, while the back is a few inches longer than that. This time around I made it with the thought in mind of actually keeping my hooks in it, and not falling out. Ergo, a longer flap, ad sewing in a bit at the opening, on both side. maybe 3/4 an inch on both sides? Ish?