Even gap is the space left over after all the hooks, split equally between and around every hook, so it looks the same edge-to-edge. Each hook's measurement below runs from the board edge (or center) you picked in "Measure from," to the point on the hook you picked in "Measure to" — the spot to mark with your tape measure. You can type the space and width above as a fraction (1 1/2) or a decimal (1.5) — whichever's easier.