The Facts: The Shimano Thunnus spinning reel is similar to the Baitrunner where it features a special lever controlled secondary drag system that acts as a tension controlled free spool. This allows the fish to take out line on the strike and then one a quick turn on the handle engages the main gears for a solid hookset. The Thunnus has an aluminum frame (graphite on the Baitrunner), more bearings, and better gearing than the Baitrunner.