The terminal gear on a trolling setup is most easily distinguished by the presence of a “downrigger,” which is a weight used to keep the lure or bait at the proper depth behind the moving boat. A variety of lures or bait – or both – are used depending on the species. Flashers and spoons are often used, to mimic the look and swimming motion of smaller prey fish. Swivels help prevent the line from twisting, and various lengths of leaders are also usually employed.
Trolling lines are usually heavy – 20 lb test or more – because of the extra tension put on them when dragged through the water using weights or a downrigger. Monofilament and braided, non-stretch lines are usually used.
Trolling rods are usually very sturdy, due to the stresses placed on them, and are both shorter and stiffer than most other fishing rods. The tips remain flexible and sensitive, to help identify when a fish bites.
Trolling reels are usually designed to be stronger than other reels, and be able to carry bigger spools with longer, heavier lines. Instead of being optimized for casting, they are optimized for pulling in larger fish from deeper waters, with special attention paid to the gear ratio and mechanism used.