The heavy duty rated, (Type IA - 300 lbs.) combines multiple ladders into one convenient ladder system. It can be configured to be used in five different ways: (1) as an A-frame ladder, (2) in the 90 degrees position for walls and tight corners, (3) on stairs and uneven surfaces as both sides telescope independently, (4) extension (straight) ladder for extra reach and (5) taken apart to form two trestles for scaffolding - Little Giant work plank sold separately. Hanging pictures or changing that impossible light bulb above the stairwell will never be easier. With its dual-layer design, you can extend the ladder height by 1-foot increments to the ideal work height of your task. It can be stored and transported at a compact height while giving you the flexibility to reach a much higher area when needed. Made of heavy-wall aircraft-grade aluminium, the Aluminium Classic Type 1A is four to five times stronger than traditional ladders The Little Giant Aluminium Classic 1A complies with all applicable OSHA & ANSI A 14.2 standards