Starting at the top of the spinning reel, the drag system is what adds or removes tension to your fishing line. A knob on top of the spool (and sometimes, in the back) allows you to adjust the frictionless plates, which increases or decreases your tension. Having this adjustability can help when fighting fish.
“So, let’s say you catch a fish, and you have a lighter drag. That gives the fish more control,” Tabrosky says. “But if you have a tighter drag, it’ll allow the fish for less control, but also increase the tension on your line.”
