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SA Amplitude Smooth Infinity Fly Line
    SA Amplitude Smooth Infinity Fly Line
    Purchase SA Amplitude Smooth Infinity Fly Line
    • SKU: sa-ampl-smth-infinity
      SA Amplitude Smooth Infinity Fly Line

    • Customer Reviews ( 44 ) Write A Review
    • $99.95

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    Scientific Anglers Amplitude Smooth Infinity Fly Line, Winner of the coveted Best Freshwater Fly Line Award at IFTD. The conventional wisdom in fly fishing is that there’s no such thing as a “do it all” freshwater line. Scientific Anglers has something to say about that. The Amplitude Smooth Infinity has the power to bomb out streamers, yet retains delicacy for dry flies. It mends like an absolute dream, and delivers flies at all distances. Built a half-size heavy, with a long head and substantial front taper, it’s perfect for everything from trout anyd panfish to pike and steelhead. There’s a reason we call it the Infinity: there is no end to what you’ll be able to do with it. The Amplitude Smooth series of lines are, simply put, the highest-performance smooth fly lines in the world. With up to five times less drag and eight times the durability of traditional lines, this will change the way you look at fly line performance.


    • Features the revolutionary AST Plus slickness additive for superior shooting ability and increased durability
    • Extremely versatile general-purpose taper designed for most freshwater species; an excellent fly line for trout, grayling, panfish, bass, carp, steelhead, salmon, and pike
    • Made a half-size heavy to load fast-action rods, but works well with a variety of rod actions
    • Extended head length for long-distance casts and superior mending ability
    • Excellent for dry flies, nymphs, and streamers
    • Available in two color schemes: standard and camo; the camo scheme features a mottled front taper for increased stealth
    • For use in moderate and cold climates
    • Braided multifilament core


    Amplitude Smooth Infinity Taper


    Cold Water Type

    Medium Water Type




    Poppers Big Dries



    WF-3-F47.0’ / 14,3m90.0’ / 27,5m110gr / 7,2g
    WF-4-F48.0’ / 14,6m90.0’ / 27,5m130gr / 8,5g
    WF-5-F49.0’ / 14,9m90.0’ / 27,5m150gr / 9,8g
    WF-6-F50.0’ / 15,2m90.0’ / 27,5m175gr / 11,2g
    WF-7-F51.0’ / 15,5m90.0’ / 27,5m200gr / 12,8g
    WF-8-F52.0’ / 15,8m90.0’ / 27,5m225gr / 14,5g
    WF-9-F53.0’ / 16,2m90.0’ / 27,5m260gr / 16,9g

    * Grain weight for the first 30′

    Rate Product
    ★★★★★ ★★★★★
    4.95/5 Stars out of 44 Reviews
    Pages 1   2   3   4   5
    Verified Buyer
    Favourite line
    David (Tongariro river) | December 1st, 2023
    My absolute favourite line for indicator fishing and dry dropper rigs
    Verified Buyer
    Great Line
    Justin (WI) | August 1st, 2023
    This line is really good . Paired with a Sage igniter 4 weight . It shoots well , turns over hopper droppers with ease , and casts very nicely .
    Verified Buyer
    Good line
    CMT (NC) | June 3rd, 2023
    Works well. Casts very nicely on my Air2. I am more of a fan of the smooth lines than the textured in general.
    Verified Buyer
    Can't say enough about this line
    Chris (Louisiana) | March 17th, 2023
    I've purchased this line in both 5wt and 7wt over the past few years, and simply can't say enough about how great this line is. Pairs beautifully with my H3F 5wt as well as my 7wt Echo Ion XL. Whether chasing trout or carp, I absolutely love this line for long delicate casts. Highly recommend.
    Verified Buyer
    Mark T (SLC, UT) | October 3rd, 2022
    The taper on this line un unmatched for quick loading. If I'm being honest, spend the extra $30 for the Textured.
    Verified Buyer
    Epic Line
    Dugan Mahoney (Missoula,MT) | August 26th, 2022
    SA continues to make great line and out performing competitors. Great product.
    Verified Buyer
    Recommend this Line
    MVK (Cheektovegas, NY) | July 27th, 2022
    Shoots and loads well. Haven't tried any chunky streamers on it, but it slings dry flies and dry droppers really well. Could not be happier with my purchase.
    Verified Buyer
    Great fly line!
    Laszlo (Texas) | July 1st, 2022
    Really like this line and most of the SA lines. Got it for my 4wt Echo carbon XL. Casts great and is not too heavy but also heavy enough to load the rod and be easy to cast. Definitely recommend this line.
    Verified Buyer
    I love this line.
    JL (East Tennessee) | June 2nd, 2022
    Clay from RFR talked me into it and I could not be happier with this purchase. Using it on a 376 Lift with an Ion reel. I wanted something to fish throughout the smokies. Casts like I know what I'm doing out there! I have the precision to place flies where I need them in tight spots, and I get better distance than I had imagined possible on those wider stretches of river. This is the second SA line I've used (MPX being the first). I cannot see myself going back to another line at this point. Great line, even better Customer Service! I love everything about RFR.
    Verified Buyer
    Excellent Line
    MVK (Cheektovegas, NY) | June 1st, 2022
    Great line, a smidge heavy but works well on my fast action rod.

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