What it is
Hareline Water Shed is a permanent waterproofing liquid you brush or soak into gear or tying materials. It dries clear, bonds to fibers as a finish, and leaves a waterproof barrier without odor. It’s non-toxic and quick-drying, so it’s easy to use at the bench and then get back to fishing.
What to tie with it
Use it to waterproof fly-tying materials like feathers and synthetic fibers before you build the fly, or as a fiber-bonding finish on already-tied sections where you want the materials to resist wetting out. It’s handy when you’re trying to keep buoyant materials from getting waterlogged or when you want to lock fibers in place without leaving a visible coating.
Flies and the fish they're for
This isn’t tied into a specific named pattern so much as it’s used to help flies and materials keep their intended behavior on the water. It’s most relevant on flies where waterlogging hurts performance, like dry flies and buoyant terrestrials for trout on rivers, and poppers or other topwater flies for bass in ponds and lakes. It can also help keep some saltwater patterns fishing higher and shedding water between casts when you’re chasing species like redfish in the flats.
How it compares
Compared to waterproofing sprays, it’s meant to avoid frequent reapplication. Unlike heat-activated treatments, it doesn’t need heat, and it’s designed to maintain breathability and flexibility without changing appearance or texture the way typical waterproofers can.