Each strand has approx 180 individual hairs that are bonded together on the ends by a keratin protein glue shape of Nail shape hair that is melted by a fusion iron or fusion iron or fusion heat wand which connected to individual section of your hair. Since these 100% human sleek hair has been cuticle aligned to ensure less tangling and durability , you can wash, dry and style just like your own hair. You may also curl, flat ironed or even color that hair. It can take anywhere from 150-250 strands for a full head of hair depending on how thick your own hair is. They last approx 3-4 months before they need to take out and redo again. Please Email Us If You Want Mix Your Color! Our Hair Are 25 Strands / Pack / Color! *Gorgeous colors especially fade easily than other special colors. Hot water makes color fade quickly. Do not expose to sun light, tanning beds or over shampooing. When you go in sun wear a hat or hair sunscreen. Always use a professional color protection shampoo and conditioner, they shield stabilize and secure color intensity to keep color treated hair fresh and radiant. DO NOT USE volume & clarifying shampoos and hair spray styling products with alcohol may also help fade color faster because it is designed to blow open the hair cuticle which sometimes accelerates hair color loss.