The pig-tail swivel hooks into an eye bolt.
Swivels allow for 360° rotation without winding up chair. Some children and adults like to wind up chairs then let go, allowing the chair to spin. This not only damages the rope and chair but is dangerous and the eyebolt can come loose from overhead and fail. Although this might be fun, winding up a hanging chair is not advised.
Certified load testing documented weight capacity of 1500 pounds for the pig-tail swivel, lag swivel and our double-eye swivel. Swivels allows you to turn your chair and relax in any direction without the chair wanting to recoil back to its neutral position. A chair with a swivel can not be wound up.
The lag-bolt swivel is for horizontal wooden beams and pigtail swivels are designed to hook into an eye hook.
WITH a chair purchase, the price is $18 with free shipping.