It is essential to use only high-quality shackles in any mooring assembly. EYE Marine recommend use of the following ‘screw pin’ types, BS 3032 Dee or Bow (manufactured to British Standard) - Green Pin Dee or Bow (manufactured to US Federal Specification) or the following ‘safety’ shackles Green Pin Dee or Bow (manufactured to US Federal Specification). We offer ‘Test Certificates’ with these types of shackle.
The best practice is to use a shackle that is at least one size larger than the chain.
These ‘low cost’ shackles are unsuitable for lifting, overhead suspension or mooring applications.
Screw pin shackles offered are generally zinc plated.
If used in a salt water environment they require very frequent inspection.
The above information is offered by EYE Marine to advise of the shortcomings of the product
Claims are made that there are some high-quality Commercial Shackles - we have yet to see one.