• The extension spring is suitable for garage doors. Such a device can eliminate the galvanized pipe, bearing support and winding wheel. The cost is relatively low and the installation is convenient. It is generally recommended for standard lifting garage doors of less than 9㎡. The material is mostly 72B.

  
  

• 1 3/4 spring is suitable for garage door and used with 1 3/4 Aluminum button sleeve.

• Double spring and single spring can be made, which is usually recommended for civil doors with any lifting mode below 12㎡. The material is mostly 72B.

• The 2 inch spring is suitable for garage door and is used with 2 inch aluminum button cover. Double spring and single spring can be made, which is usually recommended for civil doors with any lifting mode below 12㎡. The material is mostly 72B.

• The 2 5/8 spring is suitable for industrial doors and is used with 2 5/8 aluminum button sleeve. Double spring and single spring can be made, which is usually recommended for industrial doors with any lifting mode below 15㎡. The material is mostly 82B.

• 3 3/4spring is suitable for industrial doors and is used with3 3/4 Aluminum button sleeve. Double spring and single spring can be made. It is generally recommended to be used for industrial doors with any lifting mode below 25㎡. The material is mostly 82B.

Quenched steel wire

• The spring of 5 1/4 is suitable for industrial doors and is used with the aluminum button sleeve of 5 1/4. Double spring and single spring can be made, which is usually recommended for industrial doors with any lifting mode below 30㎡. The material is mostly 82B. There are quenched steel wires.

• The 6 inch spring is suitable for industrial doors and is used with 6 inch aluminum button cover. Double spring and single spring can be made, which is usually recommended for industrial doors with any lifting mode below 50㎡. The material is mostly 82B. There are quenched steel wires.

• Rolling door spring is usually used in 3 inch girder pipe and 4 inch girder pipe. Used with tubular motor with clutch. Accessories include tail insert and aluminum alloy rolling door button cover. The material is usually 72B.

For more sizes or customized garage door spring,please CONTACT with our salesman and engineer team.