Tape in hair extensions are the newest method of extensions available. They are applied using either double or single-sided polyurethane tape. With double-sided tape, the weft is applied to the hair after the backing has been removed from one side. The weft and the attached hair are pulled upwards, and another weft is applied to the other side of the tape to “sandwich” the hair. Clients with extremely thin hair, especially around the temples and side of the head, may require a single panel applied with single-sided tape.