A clevis fastener is a three piece fastener system consisting of a clevis, clevis pin, and tang. The clevis is a U-shaped piece that has holes at the end of the prongs to accept the clevis pin. The clevis pin is similar to a bolt

Bolt

-Fasteners:*A cap screw, as used in a bolted joint*Screw, a cylindrical threaded fastener*Dead bolt, a kind of locking mechanism*Bolt , an anchor point used in rock climbing-Weaponry:*Bolt , a mechanism used in firearms...

, but is only partially threaded or unthreaded with a cross-hole for a cotter pin

Cotter pin

A split pin, also known in U.S. usage as a cotter pin or cotter key, is a metal fastener with two tines that are bent during installation, similar to a staple or rivet. Typically made of thick wire with a half-circular cross section, split pins come in multiple sizes and types.The British...

. The tang is the piece that fits between the clevis and is held in place by the clevis pin. The combination of a simple clevis fitted with a pin is commonly called a shackle

Shackle

A shackle, also known as a gyve, is a U-shaped piece of metal secured with a clevis pin or bolt across the opening, or a hinged metal loop secured with a quick-release locking pin mechanism...

, although a clevis and pin is only one of the many forms a shackle may take.

Clevises are used in a wide variety of fasteners used in the farming

Agriculture

Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

 equipment, sailboat rigging

Rigging

Rigging is the apparatus through which the force of the wind is used to propel sailboats and sailing ships forward. This includes masts, yards, sails, and cordage.-Terms and classifications:...

, as well as the automotive, aircraft

Aircraft

An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...

 and construction

Construction

In the fields of architecture and civil engineering, construction is a process that consists of the building or assembling of infrastructure. Far from being a single activity, large scale construction is a feat of human multitasking...

 industries. They are also widely used to attach control surfaces and other accessories to servos in model aircraft. As a part of a fastener, a clevis provides a method of allowing rotation in some axes while restricting rotation in others.

Clevis pin

There are two main types of clevis pins: threaded and unthreaded. Unthreaded clevis pins have a domed head at one end and a cross-hole at the other end. A cotter pin

Cotter pin

A split pin, also known in U.S. usage as a cotter pin or cotter key, is a metal fastener with two tines that are bent during installation, similar to a staple or rivet. Typically made of thick wire with a half-circular cross section, split pins come in multiple sizes and types.The British...

 or split pin is used to keep the clevis pin in place. Threaded clevis pins have a partially threaded shank on one end and a formed head on the other. The formed head has a lip, which acts as a stop when threading the pin into the shackle, and a flattened tab with a cross-hole. The flattened tab allows for easy installation of the pin and the cross-hole allows the pin to be moused.

A bolt

Bolt

-Fasteners:*A cap screw, as used in a bolted joint*Screw, a cylindrical threaded fastener*Dead bolt, a kind of locking mechanism*Bolt , an anchor point used in rock climbing-Weaponry:*Bolt , a mechanism used in firearms...

 can function as a clevis pin, but a bolt is not intended to take the lateral stress that a clevis pin must handle. Normal bolts are manufactured to handled tension loads, whereas clevis pins and bolts are designed to withstand shearing forces.

Clevis pins should be closely fitted to the holes in the clevis to reduce wear and reduce the rate of failure of either the pin or the clevis.

Twist clevis

A twist shackle provides a loop at a right angle to the axis of rotation. Older implements, intended to be pulled by a team of draft animals, often require a twist shackle to be hitched.

Clevis hanger

A clevis hanger consists of one U shaped clevis, and a second V shaped clevis with a hole in a flattened section at the base of the V, joined together with a bolt or pin. Clevis hangers are generally used to hang pipes.

Clevis bracket

A clevis bracket generally form as a solid metal piece with a flat square or rectangular base, fitted with holes for bolts or machine screws, and two rounded wings in parallel forming a clevis. Commonly used in aircraft and cars, clevis brackets allow mounting of rods to flat surfaces.

Clevis hook

A clevis hook is a hook, with or without a snap lock, with a clevis and bolt or pin at the base. The clevis is used to fasten the hook to a bracket or chain.

Clevis rod end

A clevis rod end is a folded or machined piece formed into a clevis and fitted with a hole at its base to which a rod is attached. In machined pieces, the hole is most often threaded.

Twin clevis

A twin clevis is a solid piece with two clevises directly opposite one another, each fitted with a pin. Twin clevises are commonly used to join two lengths of chain.