Sew-In Hair Extensions: A stylist braids the natural hair into cornrows and then uses a needle and a thread to sew the weave extensions into the braids. The application usually takes a few hours and is recommended mainly for people with thick hair. The extensions last 6–8 weeks and shouldn’t be worn for more than 4 months. Tape-In Hair Extensions: A stylist uses a special tool to heat up professional glue and align the extensions. The treatment takes between 40–60 minutes and the effects usually last 4–8 weeks—after that time, the extensions can be removed and reinstalled.