الوصف
feature heavy-duty nylon ribbon webbing straps connected between the front and rear sections. These ribbon strings act as a safety spread-limiter, preventing the A-frame from over-extending or sliding flat when deployed on slick tiled floors.
Because it functions both as a free-standing self-supporting step stool and an extension ladder when swung open completely, this style is known locally as a Dual-Purpose Ladder (DPL).