Support posts anchored to stair threads not mounted to wallՕ Rigid aluminum extruded rail Adjustable widthbetween armrestsErgonomical up and down control buttonFlip-up seatthat swivels at top and bottomEasy access to controller and batteriesTwo obstruction sensors on carriageAnti-skid surfaceBi-directional obstruction sensor Adjustable width between armrests from 18Ք to 21 wide 457 to 533 mm ԕ Battery-powered 24-volt system Pair of 12-volt, maintenance-free batteriesՕ Electronic controller with soft start and soft stop Fused control circuitՕ Wireless infrared call/send controls at both landings...