
The first styles were made out of wood. Some were also made
out of various stamped metals, cast brass, and bronze. More modern
types are made from machined aluminum, graphite, and other lightweight
compositions.
Fly reels can be categorized into three different types; single
action reels, multiplying, and automatic.
Single action reels means that for every revolution that the handle is cranked, the same amount of line is brought in on the spool. The ratio would be 1:1.
Multiplying reels contain a gear mechanism within the reel to allow line to be retrieved more quickly. The normal ratios would be about 2:1 or 3:1.
Automatic fly reels automatically retrieves the fishing line generated by a trigger device. Because of their size and mechanisms, they are heavier, and are not used as often.
The single action reels are the most popular. They are lightweight, efficient and are a fun challenge when playing a fish, which appeals to what the sport of fly-fishing is all about.

The reel will state the size of it's diameter, which will allow you to match up with the correct line and rod size to get a general balance.
So let's say that you have a reel with a diameter of five. That simply means you should pick a weight line of five and a rod size of five. Now you have a balanced outfit.
The type of drag would depend on the type of fishing. A spring and pawl drag system would be ideal for small trout and panfish. And a disc-drag system would be ideal for other freshwater fishing game species.
Early reels had no drag at all. The angler merely used the palm of their hand to slow the fish down. Innovations now have the exposed rim that allows braking by the palm of the angler's hand. The more sophisticated drag systems are made of composite materials that feature increased adjustment range, consistency, and resistance to high temperatures from drag friction.

And a quick release button is great for changing out your spools when the situation calls for it. You may want to carry extra spools fitted with different lines rather than deal with the extra weight of other reels. Besides, a spool will obviously cost less than a reel does.
Good reels should last a lifetime with proper care and maintenance. Keep it free from sand and dirt. Store in a dust free environment or/and use a protective cover for you equipment.
Orvis
is an excellent outfitter for fly reels and for other fly-fishing
accessories. They back their products with a 100% satisfaction
guarantee. For a little fun fishing fact, Charles F. Orvis patented a
ventilated narrow spool reel in 1874.