Fly Reels -

The main key point to choosing a fly reel is to pick one that can hold the necessary amount of backing and fly line for the weight of rod that you are fishing with.  If you purchased a 5 weight fly rod, make sure you are choosing a fly reel that will accommodate fly line weights from 4-6.  Most fly reels will be available in different models to accommodate a range of fly line weights.  Just make sure that you find yours within that range.  By choosing the correct size of fly reel, you will make sure that it holds an adequate amount of backing for that time when the fish you hook makes the run of his life