Product Information: Part number SP 9637, package contains 1 SP 9637 extension spring. 1“ OD, 12” length, 0.105“ wire diameter, 35.4 lbs. maximum safe load, 11.7” maximum deflection. Please check dimensions before purchasing Product Function: It is one of the key parts in the screen door accessories, used to assist the opening and closing action of the screen door, to ensure the smooth operation of the screen door. With certain adjustment function, by adjusting the installation position or preload of the spring, it can adapt to screen doors of different weights and sizes, so that the opening and closing speed and strength of the screen door can reach the ideal state and meet the user's personalized needs Compatibility: It is also suitable for various equipments, such as electrical appliances, automobiles, boats, toys, tools, mechanical equipments, devices, chicken coops and so on High Quality: Made of durable spring steel (tempered steel wire), it provides optimal retraction when stretched and features an attractive, corrosion-resistant nickel-plated finish for both indoor and outdoor use Easy to install: SP 9637 extension springs are designed with openings for easy and reliable fixing to fixed and moving parts, greatly saving your time and effort After-sales service: your satisfaction is our pursuit, if you encounter any problems related to the product in the process of product use, you can contact us, we are happy to help you Product Information: Part number SP 9637, package contains 1 SP 9637 extension spring. 1“ OD, 12” length, 0.105“ wire diameter, 35.4 lbs. maximum safe load, 11.7” maximum deflection. Please check dimensions before purchasing Product Function: It is one of the key parts in the screen door accessories, used to assist the opening and closing action of the screen door, to ensure the smooth operation of the screen door. With certain adjustment function, by adjusting the installation position or preload of the spring, it can adapt to screen doors of different weights and sizes, so that the opening and closing speed and strength of the screen door can reach the ideal state and meet the user's personalized needs Compatibility: It is also suitable for various equipments, such as electrical appliances, automobiles, boats, toys, tools, mechanical equipments, devices, chicken coops and so on High Quality: Made of durable spring steel (tempered steel wire), it provides optimal retraction when stretched and features an attractive, corrosion-resistant nickel-plated finish for both indoor and outdoor use Easy to install: SP 9637 extension springs are designed with openings for easy and reliable fixing to fixed and moving parts, greatly saving your time and effort After-sales service: your satisfaction is our pursuit, if you encounter any problems related to the product in the process of product use, you can contact us, we are happy to help you