To know if your extensions are human hair or manufactured, look on the package or ask whoever put them in. If you can't actually FEEL a difference between your hair and the extension, chances are it's human, but there's only one way to tell for sure. Snip one of the hairs from the extensions and snip one of your own hairs and burn them. If the extension burns very differently, then it's a man-made fibre and undyeable.