A fly reel 's most important tasks are to carry your fly line, backing and tapered leader and to stop rushing fish safely. Many of today's modern fly reels have a design that includes a large spool, this spool facilitates the retrieval of fly line, which can be very important, especially when you have a fish rushing towards you.
The fly reel must also be in harmony with your fly rod, usually it is enough to buy a fly reel in the same class as your rod, but for some the balance between fly rod and fly reel is extra important, then also the weight of the roll be of interest.
Perhaps the fly reel's most important feature is its brake, this is where a slightly more expensive reel often excels. The fly reel should have a smooth and fine brake with what is called "Zero Start-Up Inertia", i.e. no jerk for the brake to start, but it starts smoothly and fine immediately.
For fly fishing in saltwater for sea trout, for example, a fly reel with an encapsulated layer is needed, this to keep the saltwater out of the reel's sensitive parts.
