Downrigger: allows you to troll at deep depths while maintaining your lure/bair to be in the strike zone of a fish. This is accomplished by using a downrigger. In essence, if is a winch (some older models are manual) hooked to a cable with a 10 or 15 pound canon ball (lead ball) at the bottom. With this canon ball comes a release clip. You clip the line in the clip on the canon ball and drop the ball to see 110 FOW where the thermacline is including thousands of baitfish and 15 pound salmon. A fish the striked the bait/lure, the release clip releases the line and signals that would have a fish by a rod giving you headshakes like crazy.