Scientific Angler Stillwater Sonar Seamless Density Full Sink Fly Line
The new Stillwater Sonar Seamless Density Full Sink Fly Lines from Scientific Anglers are blended density sinking lines designed for better contact with the fly. Featuring the revolutionary AST Plus slickness additive, these lines offer superior shooting ability and increased durability. The line is overweighted by two line weights, making it ideal for multiple flies, long leaders, and extended casts.
- Designed specifically for stillwater anglers
- Overweighted by two line weights
- Features textured hang markers at 10 feet and 20 feet from the tip
- Seamless Density technology ensures a smooth transition between densities, eliminates hinging, and provides a straight-line connection to the fly
- Intermediate/Sink 3: Designed to get under surface chop with an intermediate sink rate
| Feature | Detail |
|---|---|
| Line Type | Full Sink |
| Weight Overweight | Two line weights |
| Seamless Technology | Yes |
| Shooting Performance | Enhanced with AST Plus additive |
| Hang Markers | 10 ft and 20 ft |
FAQ
What makes the Seamless Density technology different from standard fly lines?
Seamless Density technology provides a smooth transition between densities, eliminating hinging and ensuring a straight-line connection to the fly for better performance and consistency in stillwater conditions.
How does the AST Plus additive improve line performance?
The AST Plus slickness additive enhances shooting ability and increases durability, allowing for smoother casts and longer-lasting performance under regular use.
Are the hang markers useful for fishing in stillwater?
Yes, the textured hang markers at 10 feet and 20 feet from the tip help anglers visually track the line’s position in the water, improving accuracy when casting and retrieving.



Charles Taylor –
This fly line performs well in choppy stillwater conditions. The seamless density design keeps the line straight and the fly stays in contact. The hang markers are helpful for seeing where the line is in the water. I’ve used it with multiple flies and long leaders without any issues.
Diane Nash –
The line casts smoothly and stays under the surface better than previous models. The added weight helps with long casts. The texture on the markers is noticeable and useful for positioning.
Stewart Hughes –
I’ve been using this line for several weeks in lakes with moderate surface movement. It maintains a consistent sink rate and doesn’t tangle. The AST Plus additive makes it glide well through the water.