Rite Mag (Magnum) Bobbin. Deceivers, clousers, half and half's, surf candies, some of those old classic New England streamers that sometimes call for longer shanked hooks and lots of leverage while using high strength threads like UNI Big Fly, Danville 210 or Veevus Gel Spun. For that reason, Merco developed the Mag bobbin, giving you that extended reach that can be critical to the success of some of these beefier patterns.
We've also heard that some rod builders use this bobbin, and that it accommodates some of the most popular rod-building threads like Gudebrod and Dynacord.