About This PROFESSIONAL QUALITY - Big Kizzy Nylon Weaving Thread is perfect for comfortable, long lasting human hair weft extension applications, sew in wig application, and hair replacement human hair weft applications PERFECT COLOR MATCH - Black lightweight nylon thread for hair extensions blends beautifully with very dark brown and black shades of hair for an invisible human hair weft extension application. SAFE - Nylon thread is perfect for weft extension applications! Nylon does not stretch or hold water like cotton, so it creates less stress on your natural hair and will not irritate your scalp. Super comfortable and can be worn for 2 to 3+ months with no fraying. INVISIBLE THREAD - Color match for a flawless and invisible application. If in between colors, choose the darker color that is closest to root color. Black nylon thread for human hair weft extensions blends seamlessly with all shades of very dark brown hair to black hair. COMPATIBLE: Big Kizzy Nylon hair extension weaving thread can be used with human hair hand tied weft extensions and machine sewn weft extensions. 1400m is perfect for high volume salons and hair extension specialists. Overview Material : Nylon Brand : Big Kizzy Color : Black Item Weight : 29 Grams Item Length : 3.25 Inches Product Care Instructions : Hand Wash Only UPC : 711237778593 Compatible Knitting Needle US Size : 7 Compatible Knitting Needle Metric Size : 1.5 Millimeters Line Weight : Light