Edge tape is an essential part of assembling a racket. It is a cushioned tape, that is meant to protect the edge of the racket, which is not covered by any rubber. Edge tape comes in several different widths. Choose the width of your edge tape, by adding the thicknesses of the two rubbers, and the blade. If your edge tape is too wide it will protrude over the rubber and be torn off easily. If your edge tape is not wide enough, the it will not adequately, cover the side of the racket.