Heavy duty steel construction. Zinc plated and clear coated for increased weather resistance. Very strong and can be used for a long time. The spring helps relieve stress from impacts, provides a more comfortable and softer feel, and will increase the life of your hammock, as well as your mounting surface. Compatible with almost all punching bags, boxing bags, hanging chairs, cocoon, egg chairs, wicker chairs, etc. Spring capacity rating of over 500 kilograms. 1pc Heavy Duty Extension Carabiner Hanging Hook Accessories Swing Chairs Fishing Spring Bag for Hanging Chair Hammock and Swing. - Heavy duty steel construction. Galvanized and clear coated for greater weather resistance. - The spring helps relieve stress from impacts, provides a more comfortable and softer feel, and will increase the life of your hammock, as well as your mounting surface. - Suitable for almost all punching bags, hanging chairs, cocoon, egg chair, wicker basket. Details: Item Name: Spring Hook Material: Metal Quantity: 1pcs Features: Hammock Accessories, Durable, Weather Resistance Wire Diameter: Approx. 7mm/0.3" Length: 108mm(Approx.) Package Includes: 1 x Garden Swing Springs Note: Please allow slight dimension difference due to different manual measurement. Color may vary slightly depending on your monitor settings.