Thinx are washable, reusable period underwear. Their original best-selling style now has twice the absorbency of their classic collection, as it now holds up to five regular tampon’s worth. Thinx are washable, reusable period underwear. They look and feel just like normal underwear. They keep you feeling fresh and dry with their built-in protection, are super comfy and machine washable. The super absorbency super hiphugger has a lace waistband that sits right below the natural waist.