Pair of extension springs sized 25 by 42 inches for 7-foot-high doors with open single ends. Open ends hook onto the standard extension spring hardware, which is the most common setup on residential doors. Pick the correct lift rating from the dropdown to match your door weight, which ranges from 80 to 160 pounds depending on the option. Getting the wrong lift rating means the door will not balance. Too light and the door sags, too heavy and it flies up. Always replace both springs at the same time. Weigh the door or check the manufacturer's spec to figure out which rating you need.