Scientifically Formulated to Bond XFusion Keratin Hair Fibers to Thinning Hair XFusion Fiberhold Spray is a fine mist specifically developed to increase the bond between XFusion Fibers and thinning hair. Naturally derived ingredients soften and condition both hair and fibers for a completely natural appearance. It intensifies the magnetic attraction to the hair and ensures that the fibers will stay in place in all types of conditions, even in wind, rain and perspiration You can even brush after drying for a softer style with ample fiber-holding power