Crazed, fishing fools? Line geeks? GUILTY AS CHARGED Some say we are just fanatics, using our selfish needs to create the most sophisticated, strenuously tested products available... but we call it pride... pride in the promise to give you the absolute, hands-down, best of fly fishing excellence on your rod. RIO is fanatical about technology. And our cast members have donated literally thousands and thousands of hours on the water researching, designing and refining our products. All with one goal in mind – helping anlgers hook, land and turn loose more fish!
When you rely on touch to know what’s going on in the depths, line stretch is the enemy.

Our ConnectCore full-sinking lines open up new worlds of perception and sensitivity with no-stretch performance. Soft, subtle takes become positive grabs, and without stretch to dull reaction times, hook sets are instant and sure. ConnectCore. The secret weapon for stillwater success.

Our new, ultra-sophisticated line coating redefines floating line performance. Made with a groundbreaking proprietary formula, MaxCast lines float higher, shoot farther, last longer and stay cleaner. The secret? The coating’s advanced hydrophobic chemistry, which actively pushes water away from the line, resulting in radically improved floatation and reduced dirt adhesion.

It also allows the line to slip more easily from the surface film for longer, quieter pickups. At the same time, MaxCast’s coating formulation contains a sophisticated blend of permanent slickening agents, and slickening agents that continuously migrate to the line’s exterior for enhanced shooting and durability.

Tired of floating lines that work like sink tips? Fact is, the reduced coating at the narrow, tapered end of most floating lines doesn’t have enough buoyancy to stay above water.

RIO’s MaxFloat Tips solves this age-old problem. Our all-new, proprietary tip coating formula floats more than twice as high as regular line tips, without any increase in diameter. That puts maximum floatation right where you need it for reduced drag, longer presentations and quieter pickups.

XS "Extreme Slickness" Technology

A Perfect 11

Every fly fisherman is looking for a slicker line, and for good reason. Slicker line means longer casts, which is something all anglers strive to achieve. XS Technology is the latest development from RIO's lab coats that focuses on creating an ultra slick line, with dirt-repelling tendencies.

XS (Extreme Slickness) Technology began when RIO's chemists began reformulating conventional chemical combinations. Although RIO's formulas were great, our scientists are fly fishers, and by definition they want an even slicker fly line - it's just part of the deal. So first, they tackled the polyvinyl chloride (PVC) coating and through intense scrutiny down to the polymeric mix level, (say that 10 times fast) they defined some fundamental limitations. Out went the old PVC/silicone formulas and by methodically adding a little more of this, a little less of that, and a pinch of secret sauce, the lab coats cooked up a completely new and improved recipe.

With XS Technology, RIO has developed a fly line that is slicker, more stable, and far less apt to attract dirt, and paired with AgentX Technology, it engineers a line that is less dense, casts further and more accurately, floats higher, lasts longer, and offers more consistent performance cast after cast, strike after strike, fish after fish.

How does RIO do it?

What do nonlinear dynamic deformations, numerical algorithms, non-uniform elastica, and the legendary Serret-Frenet reference frame have to do with fooling fish?

Lots, according to RIO. All the concepts, all the revolutionary tapers, all the passion in the world won’t magically turn out the world's best fly lines – you need the technology to make it happen. (Of course, real life fishing experience is required – you ever try to cast with a slide rule?) Luckily for anyone who knows everything about a caddis fly and nothing about a copolymer, RIO has done the research.

Look no further than our more recent industry-changing technologies—AgentX™ and Super Floatation Technologies™. We've all wanted a higher floating line for a long time but, even as remarkable as our fly lines are, they can’t float without a little technological intervention. Traditionally, getting a line to float has required mixing a bunch of tiny glass balls (cleverly called microspheres) into the soupy coating compound prior to the curing phase. The higher you want your line to float, the more glass balls you must add. But this creates a problem in that the microspheres can create a rougher, microscopically abrasive coating that has less plastisol which results in a structurally weaker fly line that cracks.

So, after years of experimenting with exotic compounds and plenty of waist-deep R&D, our super-smart lab people in the dust-free rooms discovered an element six times more buoyant than those made by our competitors. Six times. But the right element was just the start. It took an “exponential leap” (that’s how the labcoats talk) in rethinking the manufacturing process to put it all together. That is how RIO developed "Fusion Technology" (used in all AgentX and SFT lines). By simultaneously processing this super-buoyant undercoating with a super-smooth outer coating (remember far fewer micropheres) the results are the smoothest, most durable, and highest floating fly lines imaginable.

A customer survey performed by RIO showed that the number one complaint for fly lines was that the tip sank. RIO's chemists deduced that if one coating of AgentX was so buoyant, then two coats must be, well, really buoyant, and the end result is SFT - Super Floatation Technology. Simply put, this is a manufacturing technique that allows us to fuse two layers of buoyant AgentX coating together. This specialized process is applied to the front few feet of the fly line, producing a tip with a specific gravity of around 0.70. Compare that to the standard s. g. of 0.88 on regular fly lines and you get an idea of just how significant this is.

Better yet, go try it for yourself and see how productive fishing with a tip that stays afloat can be.

That's revolutionary.

That’s what technology and passion can do.

DualTone is a system perfected by RIO that marks the sweet spot of a fly line by providing an obvious color change in the line. The design of every fly line taper, its most likely application and each individual line size is carefully taken into account, and the location of the color change is unique to each fly line.

Every line model and size is tested on a selection of fly rods to find the ideal place where the rod loads, and the color change starts at that point.

With the DualTone system it is easy to see how much line to strip in, where to pick up a cast, how much line can be held in the air when false casting, and when to make the final cast.

The majority of modern fly lines feature a taper at the front end, which ensures that they cast smoothly and land on the water without too much impact. With sinking lines and sink tips, this taper creates a small problem; as the line gets thinner the amount of coating on it gets less. The coating is what makes a fly line sink, so as the coating is reduced, the sink rate slows down. Usually this means a tapered sinking line sinks in a curve - with the thicker, heavier and denser body section sinking faster than the tip - not good for controlling the depth, and especially not good for detecting atake, or setting the hook. RIO's Density Compensation adds a more dense material to the thin tip, which ensures the line sinks straight - better for knowing when a fish takes the fly, and far better for setting the hook. All RIO's premium tapered sinking lines and sink tips are Density Compensated.
Welded Loops RIO pioneered / originated PVC welded loops, and with the development of SFT and high floating tips, the loops eliminate water wicking up the core and sinking the line. These welded loops also enable you to smoothly and quickly rig the leader to the fly line.