Our Heat Defiant Synthetic Fiber provides beautiful volume and coverage for the crown and sides of the head. Unlike other synthetic blends, the ThinHairThick Heat Defiant Synthetic Fiber can be curled and straightened. The fine double monotop construction provides a natural scalp area all while being light and breathable. Our proprietary design application means "No Glues, No Clips, No anchors-And Best Of All, No Damage." A benefit of the Heat Defiant Synthetic Fiber is the flexibility to change your hairstyle. To curl the fiber, use a low setting on your heating tool. After curling the fiber, pin the curls in place to allow them to cool. This will set your curl. You will also enjoy the benefit of low maintenance care. Unlike human hair, HD Synthetic does not react to humidity and will not frizz. To wash, soak in a basin of cool water and add a small amount of fabric softener. Allow to soak for 30 minutes, rinse and shake dry. Of course, the biggest benefit and best part of our innovative design is the fact that you can enjoy wearing the hair with zero pain. It's all volume, no vicious!