Extension Spring Hardware Kit for 8' Doors over 300 Lbs.

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Product Description

Garage Door Extension Spring Hardware Kit. For 8' doors weighing over 300 pounds. Does not include springs.
Kit includes door cables, safety cables, 4 - 4" heavy duty cast iron pulleys, 2 - pulley forks, 2 cable adjustment clips, 2 - open eye bolts with 4 - 5/16" lock nuts, 2 - s-hooks, 4 - 3/8" X 1 1/2" hex bolts and 4 - 3/8" hex flange nuts.
IMPORTANT: Due to supply chain shortages we currently do not offer quantity discounts, and for some of our products we are limiting the quantities that may be purchased.


We are either "OUT OF" this part because it is currently unavailable, or the part is "NLA" - No Longer Available. Please contact us regarding future availability or possible substitutes for items that are no longer available.

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Huge inventory of parts and torsion springs for same or next day shipping! Here you will find all you need in the most common sizes of 1 3/4," 2," 2 1/4," and 2 5/8" inside diameter springs. Please contact us for specialty springs such as TorqueMaster, EZ Set, self-Storage, and steel rolling door springs as many of these have been subject to supply chain shortages. Larger 3 3/4" and 6" inside diameter commercial and industrial springs may require a day or two to ship.

COVID update. No mask, no service! When picking up parts please wear a mask. We'll gladly provide one. Please honor the six foot social distancing rule. Thank you for your patience and understanding.

Shipping times and costs have changed. Normal transit times are currently not guaranteed, even on next day and second day shipments. Shipping prices on items over eight feet have more than tripled.