The 40 footer is the big boy of the XRAP Magnum series, it dives to 40 feet while still being able to troll at 12 knots. These work well for anything from big yellowtail, yellowfin, bluefin and even wahoo. If you go for wahoo keep these farther back in the middle position and replace the hooks to single inlines. Guys in northern California have been using these for bluefin for a couple of years now as well as the Nomad DTX's with great success on schooling fish.