Shimano Mastiff FC Fluorocarbon Review

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Mastiff FC Fluorocarbon is one of the newest bass fishing lines to hit the market. This is Shimano’s first fishing line, however, it has been meticulously tested to bring you all the features you would come to expect in high quality fluorocarbon line. Being produced in Japan, this line is subject to a Shimano’s strict quality control. Shimano’s Mastiff FC Fluorocarbon includes innovative features and strict attention to detail, creating a high performing fluorocarbon fishing line. 




One of the biggest benefits of fluorocarbon fishing line is its strength and transparency. This style of line has managed to be thin and transparent, while still maintaining its strength. This type of fishing line also has very little stretch, making it extremely sensitive. Fluorocarbon is a great choice for a variety of bottom baits that require a strong hookset and good bottom sensitively. Fluorocarbon also sinks, giving bottom baits a faster fall rate compared to braid or monofilament lines.


Shimano’s Mastiff FC Fluorocarbon is a premium fishing line designed for tournament grade performance. This line features one of Shimano’s newest innovations, NANO ARMOR. This gives the line nano sized ridges across the outer surface. These ridges help increase knot strength and overall abrasion resistance. This is a great option when fishing bottom baits where the knot often comes in contact with the bottom. This will help decrease break offs and the amount of times you have to retie throughout the day.

While Mastiff delivers consistent strength and durability, it still remains thin and smooth. After using this line for a few weeks, I’ve noticed very little line memory. This line casts smooth without kinking after a tangle or backlash. Mastiff FC is also very thin, making it a great choice for a wide range of finesse tactics. The 10-pound test measures in at 0.26-millimeters, while the 16-pound test measures in at 0.33-millimeters. This line is offered in most sizes between 4 and 20-pound test, and is sure to handle any caliber bass you throw its way. 


I’ve been lucky enough to test this line out over the last several months, and I’ve noticed a few applications where it really shines. So far I’ve used the 12-pounds and 20-pound sizes, mainly for flipping and Damiki rig fishing. This line has specific attributes that really compliment these styles of fishing.

For flipping, I really enjoy the NANO ARMOR and increased abrasion resistance this line offers. When flipping with fluorocarbon I typically tie the snell knot, this line helps lock this knot down, which is important when tangling with big fish in heavy cover. The added abrasion resistance is also nice when fish get you wrapped about trees, docks or any other kind of cover. This has quickly became one of my favorite fluorocarbon lines for heavy cover scenarios.


While this line has been great around heavy cover, I’ve also enjoyed it in open water as well. Recently, I’ve been using the 12-pound Mastiff for my damiki rig applications and I’ve noticed a few attributes I really appreciate. This lines this diameter and impressive knot strength make it a great option for braid to fluorocarbon leaders. 

When Damiki rigging, especially with heavier heads, I typically prefer a heavier gauge line. This allows you to tighten down your drag for increased control over the fish. It also allows you to fish this bait around brush and timber without fear of breaking off. The added knot strength of Mastiff FC allows you to tighten down your drag when battling larger caliber fish without fear of the leader knot slipping. This can make a huge difference when fishing around timber or other types of heavy cover. 

Shimano Mastiff FC Fluorocarbon is a promising new line that has already been catching bass all over the country. This line’s superior knot strength and increased abrasion resistance is sure to help anglers continue to put giant fish in the boat. If you’re looking for a fluorocarbon line that is strong, smooth and transparent, Shimano FC Fluorocarbon checks all the boxes.