Screw Pin, Round Pin, or Bolt-Type Shackle
Which One Do You Need?
By Jimmy Laub - Fulcrum Lifting
Choosing the Right Shackle for Rigging Applications
Shackles are one of the most widely used components in lifting and rigging, but not all shackles are built for the same job. Choosing the right type can mean the difference between a proper lift and equipment failure.
In this article, we’ll break down the differences between screw pin shackles, round pin shackles, and bolt-type shackles—and when each is best suited for the job.
Screw Pin Shackles – Best for Quick, Temporary Use
Screw pin shackles are ideal for applications where rigging needs to be set up and taken down frequently.
Key features:
- Quick installation and removal
- Ideal for temporary or short-term use
- Not recommended in high-vibration environments
Over time, vibration or movement can loosen the pin. Always check that the pin is fully engaged before lifting.
Best uses:
- Construction sites, equipment movement, short-term lifts
Round Pin Shackles – For Tie-Downs, Not Overhead Lifting
Round pin shackles feature a smooth, unthreaded pin that is secured with a cotter pin. They are generally not recommended for overhead lifting applications because the pin can easily rotate under load and is not protected against side loading.
Key features:
- Easy to install
- Not designed for angular loads
- Should only be used for light-duty tie-down or towing applications
Best uses:
- Towing, tie-downs, light-duty load restraint (non-lifting)
Bolt-Type Shackles – Best for Long-Term or High-Vibration Lifts
Bolt-type shackles, also called safety shackles, include a bolt, nut, and cotter pin that keep the shackle secured even under vibration or shock loading.
Key features:
- More secure and tamper-resistant
- Ideal for permanent or long-term installations
- Takes longer to install—but stays secure
These are especially common in situations where the shackle won’t be removed regularly and where security is critical.
Best uses:
- Permanent rigging, offshore and marine environments, lifts subject to movement or vibration
Quick Shackles Comparison Chart
|
|
Shackle Type |
Best Use Case |
Securing Method |
Overhead Lifting |
|
|
Screw Pin |
Temporary lifts |
Threaded pin |
✅ (if properly installed) |
|
|
Round Pin |
Tie-downs/towing |
Round pin + cotter |
❌ (unless a direct line pull) |
|
|
Bolt-Type |
Long-term lifts |
Bolt + nut + cotter pin |
✅ |
Fulcrum Lifting Can Help
Still unsure which shackle is right for your application? Whether you need a few screw pin shackles for jobsite lifts or high-performance bolt-type shackles for critical rigging, Fulcrum Lifting stocks a wide variety of sizes and types, ready to ship from our warehouses.
Need help choosing the right hardware?