The Scientific Anglers Amplitude Smooth Trout GP Fly Line is the ultimate all-around performer for trout anglers who demand balance, accuracy, and durability. Designed as a general-purpose trout taper, this line is built ¼-size heavy, allowing it to load rods quickly and deliver long, accurate casts with ease. Known as “The Caster’s Fly Line,” it’s ideal for anglers who love a smooth, responsive feel while fishing dries, nymphs, or streamers. Featuring AST Plus slickness technology, the Trout GP shoots farther, floats higher, and lasts up to eight times longer than traditional fly lines.
With a mid-length head for superior mending and distance control, this line offers exceptional performance across diverse trout fishing environments—from small spring creeks to large tailwaters. The braided multifilament core ensures supple handling and consistent loop stability in both cold and moderate water temperatures, while the Improved Dry Tip keeps the front section riding high for cleaner drifts and more positive hooksets. Whether you’re casting to rising trout or working deep with nymph rigs, the Trout GP provides the perfect blend of delicacy and strength.
Enhanced with welded loops, SA•ID line identification, and the industry-leading AST Plus coating, the Amplitude Smooth Trout GP Fly Line redefines what a smooth freshwater fly line can do. It’s a favorite among serious trout anglers and ideal for species such as grayling, steelhead, bass, carp, and panfish. Simply put—it’s one of the most versatile and durable trout fly lines ever made.
| S/A AMPLITUDE SMOOTH TROUT GP FLY LINE | ||||
| Line Weight | Head Length | Total Length | Head Weight | Grain Weight* |
| WF3F | 49.5' | 90.0' | 160gr | 105gr |
| WF4F | 49.5' | 90.0' | 185gr | 125gr |
| WF5F | 50.5' | 90.0' | 220gr | 145gr |
| WF6F | 51.0' | 90.0' | 255gr | 170gr |
| WF7F | 52.0' | 90.0' | 300gr | 195gr |
| WF8F | 53.0' | 90.0' | 345gr | 220gr |
*Grain weight for first 30' of line
AST+ - Exceptionally slick and strong, Scientific Anglers Welded Loops produce smoother casts and easier turnover with a seamless fly-line-to-loop transition, making for softer landings and cleaner pickups. The sleek design also maintains buoyancy for improved fly-line flotation and enables quicker connections between fly line and leaders or fly line and backing.
Welded Loops - Exceptionally slick and strong, Scientific Anglers Welded Loops produce smoother casts and easier turnover with a seamless fly-line-to-loop transition, making for softer landings and cleaner pickups. The sleek design also maintains buoyancy for improved fly-line flotation and enables quicker connections between fly line and leaders or fly line and backing.
Improved Dry Tip - Utilizing a unique blend of microballoons, Scientific Anglers' have developed a fly-line tip section that floats twice as high as a standard line. The tip section will be floating higher with our Dry Tip Technology, which means less drag from the front of the line and more positive hook-ups.
SA Line ID - Meet the Scientific Anglers Line Identification System. SA•ID is an innovative line-marking system allowing you to identify your lines at a glance. Wonder if a shooting head is 200 grain or a 300? Just look at the SA•ID. The SA•ID can be found on the first 1-2 feet of the tip section of your line.
