Hair extensions are used in hair extension treatments and can be made of natural or synthetic (artificial) hair. The highest quality hair for extensions is made of 100% natural hair and it is, quite justifiably, significantly more expensive. With natural hair for extensions, the most natural effect is achieved, and such extended hair can be further styled and much easier to maintain. Depending on the type of extension they are intended for, extensions can be on a weft, in strands (bundle), with clips, keratin, or self-adhesive tapes.