These shackles take the place of S-hooks. Unlike S-hooks they can be used multiple times. They are also much easier to install then S-hooks. They are stronger, and some cities and parks are requiring their use instead of S-hooks. This shackle is 2 1/8” long. The ID is 3/4” and the opening is ½”. This shackle works with our swing hangers and chain except the C128 – C129 chains. This product should last 2 years in harsh conditions and up to 5 years in optimal conditions. Some conditions may require replacement sooner. Tensile strength is 8000 lbs.