Deep Wave Lace Top Closure Piece Top closures are special hair pieces which are placed on your crown area to blend right in with your hair extensions.. The top closure means that you can part your hair on the top & front of your head, this makes your hair extensions look more natural Top closures are placed at the crown of the head after hair extensions are applied for a whole head of hair look. With Lace Top Closure no one ever needs to know your wearing hair extensions. It has a natural finish & invisible appearance