Billed as a safer, more efficient alternative to site-built temporary stairs, the aluminum TeleFlight Stair System has telescoping stringers and handrails that allow it to span runs from 8 to 14 feet and rises from 61/2 to 12 feet. It weighs 750 pounds, has a load rating of 100 pounds per square foot, and comes with 18 interchangeable, easily leveled treads. It can be either rented or bought (for $8,600).

TeleFlight Stair System, 855/458-3800, teleflightstair.com.