WF and DT both SPECIFICALLY DESIGNED FOR delicate presentations of small flies to technical feeders at range with ultra-slick performance. Long taper turns over flies with delicacy and precision Built with RIO's exceptionally slick, durable SlickCast The double taper increases loop control when carrying long lengths of line Specifically designed to turn over long leaders for technical trout RIO’s TECHNICAL TROUT line features a long, taper for the lightest of presentations and delicacy and is the ideal choice of line when fishing dry flies, nymphs, soft hackles and emergers to tricky eaters at distance. The double tapered line has a long body to increase loop control when carrying long lengths, and for making precise casts to rising fish. In addition, this line is built with SlickCast, creating the slickest, most durable coating on the market—producing the least amount of friction ever measured in a fly line.