Fill In by Ellen Wille, is a 100% Remy Human Hair top piece that is designed to integrate naturally and easily with clips into your own hair. It is worn over the part of your existing hair adding volume and length. Ideal for medical crown hair loss or thinning. Fill In is enforced with a hand tied monofilament technique which creates the most natural appearance of skin like design and a soft lace front which blend seamlessly against your skin .