Scientific Anglers Frequency Series Full Sink fly line. All-purpose sinking lines. The idea behind the Frequency series is a simple one: three floating tapers, three sinking tapers, and limitless fishing options. We kept the choices easy and the prices reasonable. Why should high-performing fly lines cost so much? The short answer is that they don't have to. The only question that remains is this: What's Your Frequency? Especially effective for fishing streamersIdeal for use in stillwater situationsSink Rate: ips (Sink 3)Monofilament coreWelded loop