Edge tape holds the rubber in place (so the rubber won’t come loose from the blade). It protects the edge of the blade, and makes the racket look good. If we assemble your racket for you, we will apply edge tape at no extra charge.
Thickness
Edge tape only needs to cover the sponge, not the top sheet. So if your blade is 5 mm thick and you have two sheets of 2.0 mm rubber, you need edge tape that is 9 mm thick.