The E900 HARDWRARE SL728 28 in. Lock-End Extension Spring is a Holmes spring replacement for most one-piece garage doors. 2 x SL728 springs can handle up to a 150 pound door while 4 x SL728 springs can handle up to 300 pounds. SL728 springs are also a popular installment for lifting toy hauler doors.
- 2 x SL728-C springs support 90 lbs. to 150 lbs. garage doors
- 4 x SL728-C springs support 150 lbs. to 300 lbs. garage doors
- Length over coils: 28 in.
- Outside diameter: 1-5/16 in.
- Wire gauge: (0.177) #7
- Initial tension: 110-120
- Maximum allowable stretch: 18.5 in.
- Manufacturer warranty: 1-year