A safety catch keeps a load on the hook when the sling goes slack. A self locking hook locks positively under load and cannot be opened while the load is applied, needing a deliberate two-handed release once the load is down.
BS EN 1677-3 is the standard for self locking hooks specifically, a different certification from the 1677-2 covering ordinary sling hooks.
Temperature: this fitting is rated -40 °C to +200 °C. For work above +200 °C, the Kito ranges are rated to +400 °C.
Key Features
- Positive self locking mechanism: Locks under load, deliberate two-handed release once down
- Cobra range: Red painted finish identifies the range on site
- BS EN 1677-3: The applicable standard for this fitting type
- -40 °C to +200 °C: Check before specifying for hot work
- 9 sizes: Full data in the information sheet
- Fully marked and certificated: Grade, manufacturer’s ID, size and traceability code
Technical Specifications
| Product Code |
Chain (mm) |
A (mm) |
H (mm) |
L (mm) |
| CG8CSLH6 |
6 |
8 |
20 |
134 |
| CG8CSLH8 |
7/8 |
9.5 |
26 |
162 |
| CG8CSLH10 |
10 |
12.5 |
30 |
195 |
| CG8CSLH13 |
13 |
15 |
40 |
248 |
| CG8CSLH16 |
16 |
18.5 |
50.5 |
310 |
| CG8CSLH20 |
20 |
24 |
55 |
335 |
| CG8CSLH22 |
22 |
25 |
67 |
392 |
| CG8CSLH26 |
26 |
30 |
75 |
449 |
| CG8CSLH32 |
32 |
35 |
97 |
590 |
Working Load Limits and full dimensional data are in the information sheet.
BS EN 1677-3 | Grade 8 | -40 °C to +200 °C | LOLER Ready
Conforms to BS EN 1677-3. Grade 8 alloy steel with a red painted finish. Marked with material grade, manufacturer’s identification, size, product ID mark and traceability code, and supplied with a certificate. Rated -40 °C to +200 °C. Under LOLER 1998, thorough examination by a competent person at intervals not exceeding 12 months.
Suitable Applications
Specified wherever a hook could be knocked open or fouled, and wherever the consequence of a load coming off is severe: confined spaces, work around structure, overhead lifting where people may pass beneath.
More About This Product
Shackles are the most-handled component in any lifting operation, and that is precisely why they wear out first. A sling gets rigged and derigged; a shackle gets rigged, derigged, dropped, driven over, thrown into a box and picked up by whoever needs one. Most lifting gear fails from a single overload; shackles fail from accumulated inattention.
The grade markings matter more than most people realise. A Grade 6 high tensile shackle to BS EN 13889 and a Grade 8 alloy shackle look similar and share the same body shape, but the alloy version carries considerably more at the same size. Once a shackle is in a box with fifty others, the only way to tell them apart is the marking — which is why an unmarked shackle has to be scrapped no matter how good it looks.
Understanding the Load Path
A shackle has two distinct load-bearing elements and they do different jobs. The bow takes the sling; the pin takes the load. Reverse that — put the sling on the pin and the load on the bow — and two things happen. The sling bears on a smaller radius than it was designed for, and any movement in the sling starts to rotate the pin.
On a screw collar pin that rotation is the failure mechanism. A sling shifting under a settling load, or vibration transmitted from plant nearby, will slowly unscrew the pin over minutes or hours. It rarely happens quickly enough for anyone to see it happening.
The second consideration is angle. A shackle loaded in line with the pin carries its full rating. Loaded at an angle across the bow it carries substantially less, and published derating tables cover a limited range of angles — beyond that range no figure is published because none applies. On a multi-leg sling every leg is at an angle by definition, which is why the bow shackle exists and why putting a multi-leg sling into a dee shackle is a genuine mistake rather than a preference.
How to Use
- Match the chain size and grade: One diameter, one grade throughout the assembly.
- Confirm the mechanism locks: Engage the load and check before taking weight.
- Seat the load in the throat: Load bears in the throat, never on the tip.
- Check the temperature rating: -40 °C to +200 °C on this fitting.
- Recertify after building or altering an assembly: Proof testing and certification by a competent person is required.
- Do not modify: Never weld, heat, machine, drill or repaint.
Warning: A self locking hook that does not lock positively must be withdrawn immediately. Never force the mechanism open under load.
Safety Information
- Never exceed the marked Working Load Limit.
- Use components of the same grade throughout the assembly.
- Confirm the mechanism locks positively before every lift.
- Load must bear in the throat, never on the tip.
- Operating range -20 °C to +200 °C.
- Withdraw any fitting showing wear beyond the manufacturer’s stated limit, distortion, cracks or elongation.
- Never weld, heat treat, machine or repaint.
- Assemblies built or altered require proof testing and recertification.
- Thorough examination by a competent person required at intervals not exceeding 12 months under LOLER 1998.
Inspection and Maintenance
The locking mechanism is the whole point of the hook. Operate it repeatedly and confirm it locks positively and releases cleanly every time — a mechanism that has become vague from grit, corrosion or wear is on its way to failing. Measure the throat opening against the original dimension at every thorough examination, since throat opening is the classic evidence of overload and develops progressively rather than suddenly. Check the tip and throat bearing surfaces for gouging and wear and withdraw at the manufacturer’s stated wear limit. Confirm the safety catch springs closed under its own tension and sits against the nose with no gap. Inspect the clevis pin for straightness, wear and full engagement, and the pin bores for elongation. Confirm the grade marking and traceability code remain legible.
Downloads
Frequently Asked Questions
Q: What is the difference between this and a safety catch hook?
A safety catch stops the load falling off when the sling goes slack. A self locking hook locks positively under load and cannot be opened while loaded. Different standard: BS EN 1677-3 rather than 1677-2.
Q: How does the temperature rating compare?
This fitting is -40 °C to +200 °C. The Kito ranges run to +400 °C; Cobra and Green Pin stop at +200 °C. For foundry or heat treatment work that difference decides which range you can use.
Q: Can I mix this with other grades?
Physically yes, but the assembly must then be derated to the lower grade, marked accordingly and recertified. Simpler to keep an assembly to one grade.
Q: Why must I not repaint it?
The red finish identifies the range, and paint conceals the cracks and wear an inspection is looking for. Repainting a lifting fitting is grounds for withdrawal.
