Hi ,
I believe this drag knob will make the drag increase to be more gradual than the stock drag knob will produce , I once sent my Penn International trolling reels for drag upgrade and the technician suggested I do the more gradual increase of drag by machining the drag cam , the results were very satisfactory .
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With the ever thinning of PE line for a specified breaking strain , I think such gradual drag increase may help the angler to eliminate line breaking when increasing the drag in the hope of stopping a fast running fish .
Jon .