Crosby A336 1/2in (13MM) Lok-A-Loy 6 Connecting Link - Forged alloy steel - Quenched & Tempered. Individually Proof Tested at 2-1/2 times the Working Load Limit with certification. The Working Load Limit of the A-336 is less than Grade 80 chain ratings. When using in Grade 80 chain slings, ASME B30.9c requires that the Working Load Limit of a sling must not exceed the lowest Working Load Limit of the components in the system.