Fish hook with some form of corrosion-resistant surface coating. Corrosion resistance is required not only when hooks are used, especially in saltwater, but while they are stored. Additionally, coatings are applied to color and/or provide aesthetic value to the hook. At a minimum, hooks designed for freshwater use are coated with a clear lacquer, but hooks are also coated with gold, nickel, Teflon, tin and different colors. There are a large number of different types of fish hooks. At the macro level, there are bait hooks, fly hooks and lure hooks. Within these broad categories there are wide varieties of hook types
Fly-killing device the projectile is a perforated circular disk which, according to advertising copy, "won't splat the fly". Several similar products are sold, mostly as toys or novelty items, although their supporters maintain that they work as well as traditional fly swatters. Another gun-like design has a pair of mesh sheets spring loaded to 'clap' together when a trigger is pulled, squashing the fly between them. In contrast to the traditional flyswatter, such a design can only be used on an insect in mid-air. Another projectile fly killer is the Bug-a-Salt, a miniaturized shotgun which shoots a spray of dry table salt