escalator
metal stairs that move in a continuous loop handrails at each side of the stairs metal frames supporting the stairs a motor to drive the movement of the stairs safety sensors and switches a safety gate at the top and bottom of the escalator a control panel to activate and monitor the escalator
escalator which has metal stairs that move in a continuous loop escalator which has handrails at each side of the stairs escalator which has metal frames supporting the stairs escalator which is a motor to drive the movement of the stairs escalator which has safety sensors and switches escalator which is a safety gate at the top and bottom of the escalator escalator which is a control panel to activate and monitor the escalator