GD12192 Size: 120 lbs Heavy duty (10000 cycles) extension springs have double loop ends for extra durability, 5 sizes will replace most all spring configurations on residential doors that are no higher than 7 feet. 0.13" galvanized carbon steel aircraft cable, installed through springs to prevent injury in case of breakage. Features: -Extension spring. -Length: 25". -Size 70 lbs: Use on single car fiberglass door, 2 springs on door, 26.75"H x 1.25" W x 1.25" D. -Size 100 lbs: 27.5"H x 1.5" W x 1.5" D. -Size 120 lbs: Wood door( 8" x 7", 2 panels, 4 sections), fiberglass door(16" x 7", 4 sections. 2 springs on door), 27.5"H x 1.63" W x 1.63" D. -Size 130 lbs: Wood Door (8" x 7", 4 panels, 4 sections), 27.5"H x 1.75" W x 1.75" D. -Size 140 lbs: Wood door (9" x 7", 2 panels, 4 sections, 2 springs on door), fiberglass door(16" x 7", 2 panels, 4 springs on door), 27.5"H x 1.75" W x 1.75" D. -Size 150 lbs: Wood door (9" x 7", 4 panels, 4 sections, 2 springs per door), fiberglass door (16" x 7", 4 panels, 4 sections. 4 springs on door), 27.5"H x 1.88" W x 1.8" D. -Size 160 lbs: Wood door (9" x 7", 4 panels, 4 sections, 2 springs per door), fiberglass door (16" x 7", 4 panels, 4 sections. 4 springs on door), 27.5"H x 1.63" W x 2.5" D. gd12191 Installation gd12192 Installation gd12193 Installation gd12194 Installation gd12195 Installation