Scientific Anglers Sonar Leader – Sink 6
Imagine a world where you need to get a fly down to the fish, but all you have is a floating fly line. In that world, the perfect solution would be our SONAR Sinking Leaders. Luckily for you, we live in such a world. These 10′ leaders attach to the end of a fly line and can put your fly anywhere in the water column. With five different densities, each weighing in at 50 grains, you’ll be able to cover the surface to the depths. Ideal for single-handed lines as well as light double-handed lines, no matter the scenario, you can Get Down with SONAR.
Key Features:
- 7′ & 10′ floating and sinking leaders for use with double- and single-handed lines
- Built on 25-lb. monofilament
- Weight: 35 & 50 grains
- Welded loop on butt end
- SA ID for quick identification of individual leaders
| Feature | Detail |
|---|---|
| Length | 7′ and 10′ |
| Material | 25-lb. monofilament |
| Weight | 35 grains and 50 grains |
| End Type | Welded loop on butt end |
| Identification | SA ID marking |
FAQ
What is the difference between the 7′ and 10′ leaders?
The 7′ and 10′ leaders are both available in floating and sinking configurations. The 10′ leader provides greater reach for deeper water applications, while the 7′ leader is more suitable for shorter casts or shallower areas. Both are designed to work with single-handed and light double-handed fly lines.
What is the weight of the leader?
The leaders come in two weights: 35 grains and 50 grains. The 50-grain version provides more sink rate and is ideal for deeper water, while the 35-grain version offers a slower descent and is better for mid-water presentations.
Is the leader compatible with all types of fly lines?
Yes, these leaders are designed to work with both single-handed and light double-handed fly lines. They attach directly to the end of the fly line and are compatible with standard floating and sinking line setups.


Kylie Young –
I’ve used the 10′ sink leader in various water conditions and it performs consistently. The 50-grain weight gets the fly down quickly without tugging the line. The welded loop makes attaching it easy and the SA ID helps me keep track of which leader I’m using.
Harry Murray –
Great for when I need to reach deeper areas. The leader stays on the line without slipping and the sink rate is predictable. I use it with my single-handed setup and it’s a reliable addition to my gear.
Jasmine Black –
The 35-grain version works well for mid-water presentations. It’s not too heavy, so the fly doesn’t sink too fast. The construction feels solid and the loop is secure. I appreciate the clear SA ID marking.