RIOs GT line has been specifically designed for the demanding conditions faced by the hardcore Giant Trevally angler. Each line features a powerful front taper to cast the biggest of flies, and a short, heavy head to easily load powerful saltwater rods. The line is built on an extremely tough, ultra strong core in excess of 50 lbs that will easily battle large fish, and resist being cut on coral and rock structures. A hard, tropical coating prevents the line from wilting in the heat.

In 2016 RIO increased the core strength of the 550gr GT line to 70lb.