Strike Assist is a trolling product that allows the bait/lure to get sucked into the fish's mouth at strike, which helps anglers hook and land more fish. Without a Strike Assist, the tension from the fishing line prevents the bait/lure from moving into the fish's mouth like they expect. Strike Assist comes in two models (Model 001 and Model 002) to accommodate a range of baits/lures and trolling speeds. See the Model Selection Chart in the photos to find the model that works best for you. Model 001 has a lighter spring to maximize extension (bait/lure movement) at strike. Model 002 has a stiffer spring to accommodate baits/lures and higher trolling speeds that create more drag force.Specifications and Features: Model 001 "Spoonfeeder" Model 002 "Plugs and Cranks"