A shackle is a U-shaped, load-bearing connector with holes drilled into the ends for receiving a removable pin or bolt. In rigging and lifting, shackles are essential links that connect slings, hooks, and crane blocks to the load. They may not be the first thing you picture on a construction site, but without shackles, cranes could not lift, I-beams could not rise, and many industries would come to a standstill.

Shackles are among the most versatile and powerful pieces of material handling equipment. A single shackle can weigh from just an ounce to over four tons and can lift loads exceeding 1,500 metric tons.

What Industries Rely on Shackles?

Shackles are found across nearly every lifting and securing application, including:

• Construction
• Transportation
• Marine and offshore energy
• Land-based energy
• Power and utilities
• Oil and gas
• Cargo handling
• Infrastructure
• Mining
• Agriculture and forestry
• Towing
• Entertainment (theatrical rigging)
  

Wherever there is lifting, connecting, or securing, there are shackles.

Know Your Shackles: Types and Uses

Different applications require different shackle designs. Here are the most common types:

Remotely Operated Vehicle (ROV) Shackles
 

Designed for subsea operations, these shackles feature bright industry-standard colors for visibility and specialized handles that allow robotic manipulators to grip securely.

Theatrical Shackles

With a black finish that blends into stage backgrounds, theatrical shackles provide hidden strength for stage rigging and behind-the-scenes lifting.

Anchor Shackles

Anchor shackles have a rounded bow that allows connection of single or multiple sling legs. Their versatility makes them one of the most widely used shackles in lifting and rigging.

Wide Body Shackles

Featuring an extra-wide bow cross-section, Wide Body shackles increase the bearing surface for slings, reduce wear, and extend the life of wire rope. They are the go-to choice for heavy lifting.

Chain Shackles (Dee Shackles)

Compact in design, chain shackles are typically used with single-legged slings in tight spaces. Chain shackles have the same sideload rating as anchor shackles of appropriate pin type

Round Pin Shackles

These shackles are secured with a cotter pin that prevents the unthreaded pin from falling out. Best suited for in-line applications such as tie-downs, towing, or suspension. They should not be used with multiple sling legs or in side-loading conditions. 

Screw Pin Shackles

Screw pin shackles feature a threaded pin that screws into the body for quick connection. They can handle side loads with reduced working load limits, but care must be taken to prevent pins from rotating under load. These shackles are ideal for “pick and place” jobs.

Bolt-Type Shackles

The most secure choice for permanent or long-term installations. Bolt type shackles feature a nut and cotter system that prevents accidental loosening of the pin.  Crosby offers Easy-loc for bolt type shackles with easy assembly. They can be used in situations where round or screw pins are appropriate and are excellent for rigging applications where there’s rotation expected by the anchor bolt.

Best Practices for Shackle Applications

Proper use is critical to maximize safety and performance:

• Use bolt-type shackles for permanent or long-term connections.
• Never exceed the working load limit.
• Ensure screw pins are fully tightened before each lift.
• Always use cotter pins when required.
• Center the load in the bow to avoid side loading.
• Never connect multiple sling legs to the pin.
• Inspect shackles regularly for signs of damage, wear, or modification.
  

Shackle Inspection Checklist

Shackles must be inspected regularly and removed from service if defects are found. Look for:

• Incomplete pin engagement
• Wear or metal loss greater than 10% of original dimensions
• Heat damage or weld spatter
• Cracks, nicks, or gouges
• Excessive corrosion or pitting
• Bent or deformed components
• Damaged threads (20% or more)
• Illegible or missing identification marks
• Evidence of modification

Always reference ASME B30.26 and manufacturer guidelines for full inspection criteria.

Identification and Traceability

Every shackle should display key information directly on the bow and pin, including:

• Working Load Limit (WLL)
• Size
• Manufacturer’s name or trademark
• Traceability codes
• Material type or grade

Most Crosby Shackles incorporate markings forged into the product that serve as a guide use the QUIC-CHECK® feature. Angle indicators are forged into the shackle bow at 45 degrees angles from vertical.

The proper application of shackles requires that the correct type and size of shackle be used. Look closely on the shackle’s bow for the working load limit, its size, a traceability code, and the manufacturer’s name or trademark. Verify the bolt matches shackle grade and WLL Also, do not forget to check the pin or bolt for the name or trademark of the manufacturer, grade, material type or load rating.

Using shackles without proper markings or traceability is a serious safety risk.

Shackles Connect the World

Shackles may appear small compared to cranes and beams, but they are the backbone of safe lifting. From offshore rigs to entertainment stages, shackles connect the load to the lifting system and make modern construction and industry possible.

By knowing the different types, following proper application practices, and conducting regular inspections, rigging professionals ensure that these critical connectors do their job safely and reliably.

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For technical questions, please contact us at 1-800-220-8509 or crosbytechsupport@kitocrosby.com