Long lasting adhesive! Ultra Hold is a soft bond acrylic attachment adhesive for lace front wigs with a 3 to 6 week hold time. Optically clear non-yellowing formula used extensively in the medical industry. Perfect for poly strip and lace front hair systems and full head permanent attachments. Easy to use brush on applicator. Note: Due to the acrylic nature of this product you will experience an offensive (acrylic) smell, which will dissipate once the adhesive has dried.