Air dry, blow dry, diffuse or style - the choice is yours with this nourishing, leave-in curl serum that helps deliver high definition without the weight. Davines This Is A Curl Building Serum is a leave-in serum that helps to creating defined, bouncy curls. This curly hair serum helps your hair resist frizz by locking in moisture so curls stays soft, workable, and unbothered by bad heat and humid weather. Davines products are formulated without parabens and SLES/SLS sulfates.