Fly Hooks are hooks that are used for fly fishing. These are much smaller than normal salt water fishing hooks. They range in size, anything from 2cm in length to 4mm. Fly hooks are used in the making of fly fishing flies, the reason they are so small is that the insects replficated in fly fishing are small. It may seem as though the hooks are too small to hook fish, but they do the trick. The above answer is in relation to freshwater fly fishing - salt water fly fishing is a different story. For more information on fly fishing you can visit our site: http://www.startflyfishingnow.com