INCLUDES - 1 hammock spring, 1 pin plug, and 1 bearing. The spring and U-pin plugs are made of steel, surface treated by baking, rust-proof and corrosion-resistant. Bearing upgrade kit - The BEARING is made of steel, has excellent wear resistance, high temperature resistance, and high hardness. It can effectively increase lubrication and reduce noise. The spring can absorb vibrations when shaking, play a buffering role, increase the chair's lifespan, and make it more comfortable when shaking. WIDE RANGE OF USE - For use with almost all hanging chairs, egg chairs, porch swings, freestanding swings, hammocks, and hammock chairs. SAFER SPRING - With a load capacity of more than 500 pounds, the spring can handle the daily use of most families, which is consistent with the load capacity of common egg hanging chairs. EASY TO USE - You can see the picture for the installation sequence, the fork bolt passes through the support and connects to the spring. You can install it or replace existing ones in minutes. QUALITY GUARANTEE - Each product has been carefully checked before packaging. Satisfaction guarantee. If you are not completely satisfied, you can request a replacement product or a full refund, no questions asked.