Seemingly against the laws of nature, lightweight with the power to stop big fish are not words commonly found together in a sentence. Thunnus CI4 takes a page from Shimano's bicycle division and uses carbon materials in high-impact situations in response to anglers wanting a reel with bait-running functionality but in a lightweight body. Thunnus CI4 is up to 7 ounces lighter than its predecessor without sacrificing any power and incorporates new drag systems for the main drag as well as the baitrunner drag. Thunnus CI4 is the most efficient live bait spinning reel on the market with unmatched adjustability for fishing live bait in any condition while still having the smooth stopping power.