Forged Alloy Steel - Quenched and Tempered. Innovative cradle design allows for 100% efficiency of Grade 100 chain. Individually Proof Tested to 2-1/2 times the Working Load Limit with certification. Each hook has a Product Identification Code (PIC) for material traceability, along with the size and the name Crosby. Suitable for use with Grade 100 and Grade 80 chain. The use of A-1338 Cradle Grab Hook will allow 100 percent of the chain sling capacity. When used to hook back to chain leg to form a choker, the angle of the choke must be 120 degrees or greater. When used as a chain shortener, minimize twist of chain and ensure chain is fully engaged in hook. Fatigue rated at 1-1/2 times the Working Load Limit at 20,000 cycles. Look for the Platinum Color - Crosby Grade 100 Alloy Products.