As the name so effectively describes, these knots are put through a delicate bleaching process after being tied to the base with super tiny half knots.
This takes out most of the dark color and leaves a smaller lighter and less invisible knot that appears to be growing right from your scalp. Please note: Bleached knots does not make the knot completely invisible, it makes the knots smaller and ligher, making them less noticable. Knots are usually bleached around the perimeter.