Sturdy steel construction. Zinc plated and clear coated for added 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 sleeping surface. assembly. Compatible with almost all punching bags, punching bags, hanging chairs, cocoons, egg chairs, wicker chairs, etc. Rated spring capacity of more than 700 lbs. Contents: 2 x Carabiner. Wire Diameter: 7mm/0.3"(Approx), Length: 108mm/4.25"(Approx). 2pcs Heavy Duty Extension Carabiner Hanging Hook Accessories Swing Seats Fishing Spring Bag for Hanging Chair Hammock And Swing . - Sturdy steel frame. Galvanized and transparent coating for greater resistance to atmospheric agents. - The spring helps relieve the stress of impacts, provides a more comfortable and soft feeling and increases the life of your hammock, by more of your mounting surface. - Rated spring capacity of over 700 lbs. - Fits almost any punching bag, hanging chair, cocoon, chair egg-shaped, wicker basket. Details: Item name: spring hook Material: metal Quantity: 2 pieces Features: hammock accessories, durable, weather resistance Wire diameter: about 7mm/0.3" Length: 108mm /4.25" (approx.) Package includes: 2 x Garden Swing Springs