[FREE COLOR MATCHING SERVICE & 30 DAYS RETURN SERVICE] If you have any problems about hair secrets extensions, please contact us firstly. We will provide a satisfactory solution. We will provide a satisfactory solution. We must be take full responsibility for product quality and color difference issues. [ADJUSTABLE WIRE] If the size doesn't fit you, adjust it by tightening or loosening the wire. Each package includes a standby wire. Get beauty and confidence in seconds, instant new look and no one will find your secret. [INVISIBLE CROWN WIRE] No sewing, no glue, no tape, which is harmless to your hair. An invisible band allows the extension to lie smooth and flat on the head, making it comfortable and secure. [SECURE FIT] 2 clips already attached on the invisible hair extensions, adding security when wearing the invisible wire. PS: You can remove these 2 clips if you don't need them. [MATERIAL] Heat-friendly synthetic fiber (Heat Resistence: 300?-350? or 150-180?). With the heat-friendly fiber you can change the look using your favorite styling tools.