Read and Understand These Instructions
Before Using Hooks
Important - Basic Machining and Threading Information
Read and Follow
Crosby Hook Identification & Working Load Limit Chart §
| Hook Identification | Working Load Limit (tons) | Maximum Shank Diameter after Machining (in.) | Minimum Thread Size | |||||
| 319-C 320-CN 320-C 322-C | 319-A 320-AN 320-A 322-A | 319-B | 319-C 320-CN 320-C 322-C | 319-A 320-AN 320-A 322-A | 319-B | 319-C (Carbon) | 319-A
(Alloy) 319-B (Bronze) | |
| DC | DA | DB | .75 | 1 | .5 | .53 | 1/2-13 unc | 1/2-13 unc |
| FC | FA | FB | 1 | 1.5 | .6 | .62 | 5/8-11 unc | 5/8-11 unc |
| GC | GA | GB | 1.5 | 2 | 1 | .66 | 5/8-11 unc | 5/8-11 unc |
| HC | HA | HB | 2 | 3 | 1.4 | .81 | 3/4-10 unc | 3/4-10 unc |
| IC | IA | IB | 3 | *4.5 / 5 | 2.0 | 1.03 | 7/8-9 unc | 7/8-9 unc |
| JC | JA | JB | 5 | 7 | 3.5 | 1.27 | 1 1/8-7 unc | 1 3/8-7 unc |
| KC | KA | KB | 7.5 | 11 | 5.0 | 1.52 | 1 1/4-7 unc | 1 3/8-6 unc |
| LC | LA | LB | 10 | 15 | 6.5 | 1.75 | 1 5/8-8 unc | 1 5/8-8 unc |
| NC | NA | NB | 15 | 22 | 10 | 2.00 | 2-8 unc | 2-8 unc |
| OC | OA | OB | 20 | 30 | 13 | 2.50 | 2 1/4-8 unc | 2 1/4-8 unc |
| PC | PA | - | 25 | 37 | - | 3.50 | 2 3/4-8 unc | 2 3/4-8 unc |
| SC | SA | - | 30 | 45 | - | 3.50 | 3-8 unc | 3-8 unc |
| TC | TA | - | 40 | 60 | - | 4.00 | 3 1/4-8 unc | 3 1/2-8 unc |
| UC | UA | - | 50 | 75 | - | 4.50 | 3 3/4-8 unc | 4-4 unc |
| - | WA | - | - | 100 | - | 6.12 | - | 4 1/2-8 unc |
| - | XA | - | - | 150 | - | 6.38 | - | 5 1/2-8 unc |
| - | YA | - | - | 200 | - | 7.00 | - | 6 1/4-8 unc |
| - | ZA | - | - | 300 | - | 8.62 | - | 7 1/2-8 unc |
* New 320-AN is rated at 5 tons.
§ Working Load Limit - The maximum mass or force which the product is authorized to support in general service
when the pull is applied in-line, unless noted otherwise, with respect to the centerline of the product. This term is
used interchangeably with the folowing terms:
1. WLL 2. Rated Load Value 3. SWL 4. Safe Working Load 5. Resultant Safe Working Load.