What tool is used to secure hair within the link when applying hair extensions?

The tool used to secure hair within the link when applying hair extensions is needle-nose pliers. These specialized pliers are designed to grip small items tightly and allow for precise control when handling hair extension links or beads. When applying hair extensions, it's crucial to ensure that the hair strands are securely held in place to avoid slippage and maintain the longevity of the extensions. Needle-nose pliers provide the necessary leverage to effectively squeeze the link around the hair strands, ensuring a secure attachment.

Other tools, such as scissors, brushes, and combs, serve different purposes in the hair extension process. Scissors are commonly used for cutting hair or trimming extensions but are not suitable for securing the links. Brushes and combs are essential for detangling and styling the hair, but they don't have the gripping capability needed to properly secure hair extensions within the links. Thus, needle-nose pliers remain the optimal tool for this specific task.