40mm

Step 1: Measure your window(use measurement guide to assist)

Step 2: Take down your measurements in width and height

Step 3: Select the drop down menu that says “select size”

Step 4: Find your closest width(numbers that appear first) and closest height(numbers that appear second) to what you have measured

Select the width and height that is slightly more than your current measurement if the blinds will sit on the outside of your window frame

Select the width and height that is slight less than your current measurements if the blinds will sit inside the window frame