Super Series Reels spools are 100% interchangeable with spools of comparably-sized standard Abel Big Game Reels. We call that InterchangeABELity. You'll call it a miracle. Essentially, it gives you two totally different reels with different line capacities at the price of 1-1/2.
Example: Consider a Super 8 reel and Big Game #3 spare spool. The Super 8 holds an 8-weight line with 200 yards of 20# backing, the perfect weapon for bonefish, school stripers and reds; while the interchangeable #3 spool will hold a 12-weight line plus 250 yards of 30# backing, or 500 yards of 50# Spectra, for tarpon and sailfish.