Cable Drum Set, Includes Standard Steel Set Screws, For Use With Mfr. Model Number 1 in Shaft, Commercial Vertical Lift Garage Doors, Lifting Weight Per Drum 660 lb, Maximum Door Height 18 ft 1 in, Type Specialty Coated Die Cast Aluminum, For Use With Commercial Vertical Lift Garage Doors, 1 in Shaft, Maximum Door Height 18 ft 1 in , Lifting Weight Per Drum 660 lb, 1 Pair