In skateboarding

Skateboarding

Skateboarding is an action sport which involves riding and performing tricks using a skateboard.Skateboarding can be a recreational activity, an art form, a job, or a method of transportation. Skateboarding has been shaped and influenced by many skateboarders throughout the years. A 2002 report...

 and related sports, skyhooks are devices which serve as semi-open bindings. They are usually made of aluminium

Aluminium

Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....

, steel

Steel

Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

  or hard plastic

Plastic

A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs...

 and are formed to cover the rider's boot, yet to allow him to easily free his feet from the hook. They may be screwed to the top of the board to facilitate jumping and enhance stability during a ride.

They are mostly used on freeboard

Freeboard (skateboard)

A freeboard is kind of specialist skateboard designed to closely simulate the behavior of a snowboard.It has 6 wheels, two spring locked center wheels, and four slightly raised conventional wheels. The central axis wheels are able to turn freely in all directions, which allows the freeboard to...

s and longboard

Longboard (skateboard)

A longboard is a surfing variant of a skateboard, similar and related to a surfboard or snowboard with wheels. It is used for cruising, downhill racing, slalom racing, sliding, and/or transport. However, most stunts, and the boards themselves are very different from that of a typical skateboard...

s without a kicktail

Kicktail

Kicktails are the upwards bent tips of a skateboard deck, today considered vital to a skateboard. The front kicktail is usually called the nose while the back kicktail is referred to as the tail. Kicktails are nowadays key to maneuvering the board, especially in street skating.-History:As the name...

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