Size/range grading is where you would include what sizes the product is, and the plus and minus icons you can use to add or remove to get the correct amount you need.     To add more size range/ grading tap the plus icon.     When you have the correct number of cells for the sizes, you can now enter them, selecting which will be your sample size, by tapping the circle icon, then tapping the apply button to save your size range gradings.