RIO Skagit Max heads cast large flies and the fastest of sinking tips with exceptional ease. The unique weight distribution deeply loads rods for long, powerful casts, while the subtle taper design generates smooth, easy loops. All Skagit heads are built on an ultra-low stretch core for the maximum in casting and fishing sensitivity. For best performance, RIO recommends attaching the following head sizes to these shooting lines sizes: 200 to 400 gr - .024"/.026" shooting line, or 25lb SlickShooter/GripShooter. 400 to 550 gr - .030"/.032" shooting line or 35lb SlickShooter/GripShooter. 550 to 675 gr - .035"/.037" shooting line, or 44lb SlickShooter/GripShooter. 675 gr and heavier - .040"/.042" shooting line or 50lb SlickShooter/GripShooter Easy Casting, Ultra-PowerfulHeads For Big Flies And Sink TipsPowerful front end to easily cast large fliesand fast sinking tipsUltra-low stretch core for the best in castingand fishing sensitivityComplete series of heads with varying lengthsand small size incrementsExtreme Slickness with ConnectCore. Easy ID loops with front and back loop.