Loon Fluorescing Hard HeadA THICK HEAD CEMENT THAT ADDS A FLUORESCING ELEMENT TO FLIES, MAKING THEM MORE VISIBLE UNDERWATER At depths as shallow as a few feet, even bright flies can appear dull and disappear into the background in the dark underwater world. Loon Fluorescing Hard Head performs just like Hard Head Clear, and takes the UV light that is available underwater and reflects it as a color more visible to fish. FEATURES Thick head cement Dries hard and with a high gloss