» For the equipment used in dog competitions, see dog agility. For the house style, see A-Frame house. An A-frame is a basic structure designed to bear a load in a lightweight economical manner. The simplest form of an A-frame is two similarly sized beams, arranged in a 45-degree or greater angle, attached at the top. These materials are often wooden or steel beams attached at the top by rope, welding, gluing, or riveting. Due to having only two "legs", A-frames are usually set up in rows so t… (More on A-frame)