A tungsten impregnated coated hooklink which is is based from Gardner's very popular ultra skin, it is nice and supple but incredibly strong and heavy too.
When pure brute strength is what you need, look no further than the Gardner HydroTUFF, this gear will not let you down and is a lot of big fish anglers go to mainline.
These swivels are perfect for a variety of uses from constructing hinge rigs to slotting inside inline leads to using on chod rigs either on leadcore or on the naked mainline.