Keratin Tip Hair is also called "pre-bonded or pre-glued hair extensions" has adhesive tipped on each strand section and can be easily applied. The strands are made with precise amounts of hair to provide the best coverage with a minimum of bulk. Since the adhesive is already applied, less time is needed to install the hair and the strands are more evenly distributed for greater flexibility and natural flow.Pre-bonded hair can be used with most heat connectors but I tipped pre-bonded hair extensions can be also applied with micro rings.