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Garage door extension springs are made specifically for a door height. For example, extension springs for 7' high garage doors generally cannot be used with 8' doors. When you use an extension spring with a taller door, the spring will have to stretch farther to allow the door to close. This affects the lift of the springs as well as how long the spring will last.
Garage door opener remotes, receivers, keypads, eyes, control stations, trollys, limit switches, gears, sprockets, v-belts, capacitors, cords, batteries, and pneumatic controls for use with Chamberlain LiftMaster (Security+, Billion Code and Digital series), Genie (including Intellicode technology), Multi-Code, Digi-Code and Allstar (including the MVP series) openers they all are ready to upgrading and usage.