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. It is made of C45 forged steel. This shackle is 5/16” with 3/8” x 1 ½” bolt. This shackle is 5/16” with 3/8” x 1 ½” bolt. There is a ½” opening at the bolt and at the widest it is 1”. This will accept up to a ½” chain. This shackle works with our swing hangers nad chain except the C125 green, C126, C127 red and the C128. The shackle is 212 HBS and the bolt is 176 HBS. 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 12500 lbs.