The D5920-2 20 Feet Fiberglass Extension Ladders Feature A Rounded Rail For Improved Ergonomics While Climbing And Carrying. The Non-Conductive Fiberglass Rails Are Interlocking And The Exclusive Alflo Rung Joint Means Twist-Proof Performance Every Time. The Traction-Tred D Rungs Are Slip Resistant. These Extension Ladders Are Lightweight For Transporting And Maneuvering Yet Still Have A Duty Rating Of 225 Lbs.