Current tracking baseline. No price change recorded.
Since 16 October 2026
Scientific Anglers Amplitude Smooth Infinity Optic Weight Forward Fly Line
Lowest in-stock price
£109.90
from Fishing Tackle & Bait
Compared across 2 shops, with 2 currently in stock
Product Information
The Scientific Anglers Amplitude Smooth Infinity Optic is a weight-forward floating fly line for freshwater fishing. Its general-purpose taper is for trout, grayling, panfish, bass and carp, while it is made half a size heavy to load fast-action rods.
It also covers pike and steelhead.
A long head and substantial front taper support long-distance casting and mending. AST Plus is a slickness additive that improves shooting ability and durability, while the line has up to five times less drag and eight times the durability of traditional lines.
It has the power for streamers while staying delicate enough for dry flies, and is also suitable for nymphs. The #6 has a 50ft head and the #7 a 51ft head, with both lines measuring 90ft overall.
Features and Specifications
| Feature | Details |
|---|---|
| Line weights | #6 and #7 |
| Head length | #6 50ft / 15.2m, #7 51ft / 15.5m |
| Total length | 90ft / 27.5m |
| Head weight | #6 265gr / 17.2g, #7 305gr / 19.8g |
| First 30ft grain weight | #6 175gr / 11.2g, #7 200gr / 12.8g |
| Line type | Weight-forward floating |
| Taper build | Half-size heavy, long head and substantial front taper |
| Slickness additive | AST Plus |
| Rod actions | Fast-action rods and a variety of rod actions |
| Fly types | Dry flies, nymphs and streamers |
| Climate | Moderate and cold climates |
Price History
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Frequently Asked Questions
Which line weights does Amplitude Smooth Infinity Optic come in?
It comes in #6 and #7 weights.
How long are Amplitude Smooth Infinity Optic #6 and #7 lines?
Both lines measure 90ft overall. Their heads measure 50ft and 51ft respectively.
Is Amplitude Smooth Infinity Optic suitable for dry flies and streamers?
It is suitable for dry flies, nymphs and streamers.
What rod actions does Amplitude Smooth Infinity Optic work with?
It loads fast-action rods and works with a variety of rod actions.
What climates is Amplitude Smooth Infinity Optic made for?
It is for moderate and cold climates.
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