Making precise casts to wary bonefish and tarpon in calm, clear flats requires a line with some added finesse. The RIO Directcore Flats Pro Fly Line delivers with a mid-length head that can be cast long distances, without losing control or accuracy in the process. Taper aside, RIO built its new flagship saltwater line around its Directcore technology, which retains its shape and stiffness after a full day of casting in hot, humid coastal environments.