Power load line and backing onto large arbor type fly reels. Large 5.5 inch outside diameter. No adjustments needed to fit a wide range of large arbor type fly reels. Eliminates considerable time and effort to wind line and backing onto fly reels. Will not mark or scratch fly reels. Requires 7/16" nut driver not included. (Fits most reels with an outside diameter of 3 ¼” or larger)