Some human hair systems last longer than others, but on average between 6 and 18 months. This is sometimes because the attachment (keratin bond) breaks, because the extensions are connected to your hair and as they grow they will get loose (approximately 0.4″ per month). Depending on how fast your hair grows and how well you take care of your extensions they have to be removed or tightened or re-bonded when they get too loose. With our hair extensions it is possible to reuse the hair. The ability to reuse depends on the hair quality and how well you take care of it. Our quality is unmatched, and each bundle is 100 grams.