Premium Quality Material: This self-closing gate spring is made of heavy-duty steel with a black powder coating for corrosion resistance, rustproof, not easy to crack, and durable for long-term outdoor use. It now solves the problem of easy breakage at the soldered joint. Adjustable Spring Tension: The gate spring can adjust the spring tension by using the locking pin and adjustment tool (included) to control the closing speed. The self-locking door spring is designed to automatically close doors or gates to ensure convenience and security. Easy to Install: The door spring hardware kit includes mounting instructions and hardware to help you install it easily. Simply attach one side of the spring to the post and the other side to the gate or door. NOTE: Be careful not to overtighten the screws if installing a vinyl fence. Wide Application: The adjustable gate spring is suitable for outdoor vinyl doors, agricultural fences, garden fences, sheds, lawns, cabins, orchards, decks, pools, square wooden posts, and various wooden gates. It provides convenience and a sense of security for you every time, and helps you close the door automatically. Package Includes: The length of the automatic door closing spring is 14\". All hardware and instructions are included: 1 x 14\" spring-loaded door closer, 1 x positioning pin, 1 x adjustment pin, 4 x 1\" screws, designed for left- and right-swinging doors, suitable for heavy and light loads.