Foundry hooks are unique because they offer an exceptionally wide throat opening which makes them capable of fitting around many large objects that standard slings hooks simply cannot accommodate. They are also somewhat controversial because they do not feature a safety latch, yet they are made and designed for overhead lifting with Grade 100 chain slings. From our conversations with OR-OSHA field personnel, this is acceptable. Just make sure to follow the Working Load Limits and use limitations provided by the manufacturer. Proof-tested and certified with a 4:1 safety factor.